Package com.sun.jna

## Class Native

- java.lang.Object
- - com.sun.jna.Native

All Implemented Interfaces:
  `Version`

    public final class Native
    extends java.lang.Object
    implements Version

Provides generation of invocation plumbing for a defined native library interface. Also provides various utilities for native operations.

`getTypeMapper(java.lang.Class<?>)` and `getStructureAlignment(java.lang.Class<?>)` are provided to avoid having to explicitly pass these parameters to `Structure`s, which would require every `Structure` which requires custom mapping or alignment to define a constructor and pass parameters to the superclass. To avoid lots of boilerplate, the base `Structure` constructor figures out these properties based on its enclosing interface.

## Library Loading

When JNA classes are loaded, the native shared library (jnidispatch) is loaded as well. An attempt is made to load it from the any paths defined in `jna.boot.library.path` (if defined), then the system library path using `System.loadLibrary(java.lang.String)`, unless `jna.nosys=true`. If not found, the appropriate library will be extracted from the class path (into a temporary directory if found within a jar file) and loaded from there, unless `jna.noclasspath=true`. If your system has additional security constraints regarding execution or load of files (SELinux, for example), you should probably install the native library in an accessible location and configure your system accordingly, rather than relying on JNA to extract the library from its own jar file.

To avoid the automatic unpacking (in situations where you want to force a failure if the JNA native library is not properly installed on the system), set the system property `jna.nounpack=true`.

While this class and its corresponding native library are loaded, the system property `jna.loaded` will be set. The property will be cleared when native support has been unloaded (i.e. the Native class and its underlying native support has been GC'd).

NOTE: all native functions are provided within this class to ensure that all other JNA-provided classes and objects are GC'd and/or finalized/disposed before this class is disposed and/or removed from memory (most notably Memory and any other class which by default frees its resources in a finalizer).

## Native Library Loading

Native libraries loaded via `load(Class)` may be found in several locations.

Author:
  Todd Fast, todd.fast@sun.com, twall@users.sf.net
See Also:
  `Library`

### Nested Class Summary

Nested Classes
`static interface` `Native.ffi_callback`

### Field Summary

Fields
`static int` `BOOL_SIZE` Size of a native `bool` type (C99 and later), in bytes.
`(package private) static int` `CB_HAS_INITIALIZER` Indicates whether the callback has an initializer.
`(package private) static int` `CB_OPTION_DIRECT` Use direct mapping for callback.
`(package private) static int` `CB_OPTION_IN_DLL` Return a DLL-resident fucntion pointer.
`static boolean` `DEBUG_JNA_LOAD`
`static boolean` `DEBUG_LOAD`
`static java.nio.charset.Charset` `DEFAULT_CHARSET`
`static java.lang.String` `DEFAULT_ENCODING`
`(package private) static java.lang.String` `JNA_TMPLIB_PREFIX`
`(package private) static java.lang.String` `jnidispatchPath`
`static int` `LONG_DOUBLE_SIZE` Size of a native `long double` type (C99 and later), in bytes.
`static int` `LONG_SIZE` Size of a native `long` type, in bytes.
`(package private) static int` `MAX_ALIGNMENT`
`(package private) static int` `MAX_PADDING`
`static int` `POINTER_SIZE` The size of a native pointer (`void*`) on the current platform, in bytes.
`static int` `SIZE_T_SIZE` Size of a native `size_t` type, in bytes.
`static int` `WCHAR_SIZE` Size of a native `wchar_t` type, in bytes.

### Fields inherited from interface com.sun.jna.Version

`VERSION, VERSION_NATIVE`

### Method Summary

All Methods Static Methods Concrete Methods Deprecated Methods
`(package private) static void` `close​(long handle)` Close the given native library.
`(package private) static long` `createNativeCallback​(Callback callback, java.lang.reflect.Method method, java.lang.Class<?>[] parameterTypes, java.lang.Class<?> returnType, int callingConvention, int flags, java.lang.String encoding)` Create a native trampoline to delegate execution to the Java callback.
`(package private) static boolean` `deleteLibrary​(java.io.File lib)` Remove any automatically unpacked native library.
`static void` `detach​(boolean detach)` Indicate whether the JVM should detach the current native thread when the current Java code finishes execution.
`static java.io.File` `extractFromResourcePath​(java.lang.String name)` Attempt to extract a native library from the current resource path, using the current thread context class loader.
`static java.io.File` `extractFromResourcePath​(java.lang.String name, java.lang.ClassLoader loader)` Attempt to extract a native library from the resource path using the given class loader.
`static void` `ffi_call​(long cif, long fptr, long resp, long args)` Make an FFI function call.
`static void` `ffi_free_closure​(long closure)`
`static long` `ffi_prep_cif​(int abi, int nargs, long ffi_return_type, long ffi_types)` Create a new cif structure.
`static long` `ffi_prep_closure​(long cif, Native.ffi_callback cb)`
`(package private) static java.lang.Class<?>` `findDirectMappedClass​(java.lang.Class<?> cls)` Find the nearest enclosing class with native methods.
`(package private) static java.lang.Class<?>` `findEnclosingLibraryClass​(java.lang.Class<?> cls)` Find the library interface corresponding to the given class.
`(package private) static long` `findSymbol​(long handle, java.lang.String name)`
`static void` `free​(long ptr)` Call the real native free
`(package private) static void` `freeNativeCallback​(long ptr)` Free the given callback trampoline.
`(package private) static byte` `getByte​(Pointer pointer, long baseaddr, long offset)`
`(package private) static byte[]` `getBytes​(java.lang.String s)`
`(package private) static byte[]` `getBytes​(java.lang.String s, java.lang.String encoding)`
`(package private) static byte[]` `getBytes​(java.lang.String s, java.nio.charset.Charset charset)`
`static Callback.UncaughtExceptionHandler` `getCallbackExceptionHandler()`
`(package private) static java.lang.Class<?>` `getCallingClass()` Try to determine the class context in which a `register(String)` call was made.
`(package private) static char` `getChar​(Pointer pointer, long baseaddr, long offset)`
`static long` `getComponentID​(java.awt.Component c)` Utility method to get the native window ID for a heavyweight Java `Component` as a `long` value.
`static Pointer` `getComponentPointer​(java.awt.Component c)` Utility method to get the native window pointer for a heavyweight Java `Component` as a `Pointer` value.
`static java.lang.String` `getDefaultStringEncoding()`
`static Pointer` `getDirectBufferPointer​(java.nio.Buffer b)` Convert a direct `Buffer` into a `Pointer`.
`(package private) static java.nio.ByteBuffer` `getDirectByteBuffer​(Pointer pointer, long addr, long offset, long length)`
`(package private) static double` `getDouble​(Pointer pointer, long baseaddr, long offset)`
`(package private) static float` `getFloat​(Pointer pointer, long baseaddr, long offset)`
`(package private) static int` `getInt​(Pointer pointer, long baseaddr, long offset)`
`static int` `getLastError()` Retrieve last error set by the OS.
`static java.util.Map<java.lang.String,​java.lang.Object>` `getLibraryOptions​(java.lang.Class<?> type)` Return the preferred native library configuration options for the given class.
`(package private) static long` `getLong​(Pointer pointer, long baseaddr, long offset)`
`static int` `getNativeSize​(java.lang.Class<?> cls)` Returns the native size for a given Java class.
`static int` `getNativeSize​(java.lang.Class<?> type, java.lang.Object value)`
`(package private) static Pointer` `getPointer​(long addr)`
`(package private) static short` `getShort​(Pointer pointer, long baseaddr, long offset)`
`(package private) static java.lang.String` `getSignature​(java.lang.Class<?> cls)`
`(package private) static java.lang.String` `getString​(Pointer pointer, long offset)`
`(package private) static java.lang.String` `getString​(Pointer pointer, long offset, java.lang.String encoding)`
`(package private) static byte[]` `getStringBytes​(Pointer pointer, long baseaddr, long offset)`
`static java.lang.String` `getStringEncoding​(java.lang.Class<?> cls)`
`static int` `getStructureAlignment​(java.lang.Class<?> cls)`
`(package private) static java.io.File` `getTempDir()` Obtain a directory suitable for writing JNA-specific temporary files.
`(package private) static Pointer` `getTerminationFlag​(java.lang.Thread t)`
`static TypeMapper` `getTypeMapper​(java.lang.Class<?> cls)` Return the preferred `TypeMapper` for the given native interface.
`static java.lang.String` `getWebStartLibraryPath​(java.lang.String libName)` If running web start, determine the location of a given native library.
`(package private) static java.lang.String` `getWideString​(Pointer pointer, long baseaddr, long offset)`
`(package private) static long` `getWindowHandle0​(java.awt.Component c)`
`static long` `getWindowID​(java.awt.Window w)` Utility method to get the native window ID for a Java `Window` as a `long` value.
`static Pointer` `getWindowPointer​(java.awt.Window w)` Utility method to get the native window pointer for a Java `Window` as a `Pointer` value.
`(package private) static long` `indexOf​(Pointer pointer, long baseaddr, long offset, byte value)`
`(package private) static int` `initialize_ffi_type​(long type_info)` Returns the size (calculated by libffi) of the given type.
`(package private) static double` `invokeDouble​(Function function, long fp, int callFlags, java.lang.Object[] args)` Call the native function.
`(package private) static float` `invokeFloat​(Function function, long fp, int callFlags, java.lang.Object[] args)` Call the native function.
`(package private) static int` `invokeInt​(Function function, long fp, int callFlags, java.lang.Object[] args)` Call the native function.
`(package private) static long` `invokeLong​(Function function, long fp, int callFlags, java.lang.Object[] args)` Call the native function.
`(package private) static java.lang.Object` `invokeObject​(Function function, long fp, int callFlags, java.lang.Object[] args)` Call the native function, returning a Java `Object`.
`(package private) static long` `invokePointer​(Function function, long fp, int callFlags, java.lang.Object[] args)` Call the native function.
`(package private) static Structure` `invokeStructure​(Function function, long fp, int callFlags, java.lang.Object[] args, Structure s)` Call the native function, returning a struct by value.
`(package private) static void` `invokeVoid​(Function function, long fp, int callFlags, java.lang.Object[] args)` Call the native function.
`(package private) static boolean` `isCompatibleVersion​(java.lang.String expectedVersion, java.lang.String nativeVersion)` Version string must have the structure <major>.<minor>.<revision> a bugfix change in the native code increments revision, the minor is incremented for backwards compatible changes and the major version is changed for backwards incompatbile changes.
`static boolean` `isProtected()` Returns whether protection is enabled.
`static boolean` `isSupportedNativeType​(java.lang.Class<?> cls)`
`(package private) static boolean` `isUnpacked​(java.io.File file)` Identify temporary files unpacked from classpath jar files.
`static <T extends Library> T` `load​(java.lang.Class<T> interfaceClass)` Map a library interface to the current process, providing the explicit interface class.
`static <T extends Library> T` `load​(java.lang.Class<T> interfaceClass, java.util.Map<java.lang.String,​?> options)` Map a library interface to the current process, providing the explicit interface class.
`static <T extends Library> T` `load​(java.lang.String name, java.lang.Class<T> interfaceClass)` Map a library interface to the given shared library, providing the explicit interface class.
`static <T extends Library> T` `load​(java.lang.String name, java.lang.Class<T> interfaceClass, java.util.Map<java.lang.String,​?> options)` Load a library interface from the given shared library, providing the explicit interface class and a map of options for the library.
`static <T> T` `loadLibrary​(java.lang.Class<T> interfaceClass)` Deprecated.
`static <T> T` `loadLibrary​(java.lang.Class<T> interfaceClass, java.util.Map<java.lang.String,​?> options)` Deprecated.
`static <T> T` `loadLibrary​(java.lang.String name, java.lang.Class<T> interfaceClass)` Deprecated.
`static <T> T` `loadLibrary​(java.lang.String name, java.lang.Class<T> interfaceClass, java.util.Map<java.lang.String,​?> options)` Deprecated.
`static void` `main​(java.lang.String[] args)` Prints JNA library details to the console.
`static long` `malloc​(long size)` Call the real native malloc
`(package private) static void` `markTemporaryFile​(java.io.File file)` Perform cleanup of automatically unpacked native shared library.
`(package private) static long` `open​(java.lang.String name)` Open the requested native library with default options.
`(package private) static long` `open​(java.lang.String name, int flags)` Open the requested native library with the specified platform-specific otions.
`(package private) static void` `read​(Pointer pointer, long baseaddr, long offset, byte[] buf, int index, int length)`
`(package private) static void` `read​(Pointer pointer, long baseaddr, long offset, char[] buf, int index, int length)`
`(package private) static void` `read​(Pointer pointer, long baseaddr, long offset, double[] buf, int index, int length)`
`(package private) static void` `read​(Pointer pointer, long baseaddr, long offset, float[] buf, int index, int length)`
`(package private) static void` `read​(Pointer pointer, long baseaddr, long offset, int[] buf, int index, int length)`
`(package private) static void` `read​(Pointer pointer, long baseaddr, long offset, long[] buf, int index, int length)`
`(package private) static void` `read​(Pointer pointer, long baseaddr, long offset, short[] buf, int index, int length)`
`static void` `register​(NativeLibrary lib)` When called from a class static initializer, maps all native methods found within that class to native libraries via the JNA raw calling interface.
`static void` `register​(java.lang.Class<?> cls, NativeLibrary lib)` When called from a class static initializer, maps all native methods found within that class to native libraries via the JNA raw calling interface.
`static void` `register​(java.lang.Class<?> cls, java.lang.String libName)` When called from a class static initializer, maps all native methods found within that class to native libraries via the JNA raw calling interface.
`static void` `register​(java.lang.String libName)` When called from a class static initializer, maps all native methods found within that class to native libraries via the JNA raw calling interface.
`static boolean` `registered​(java.lang.Class<?> cls)`
`(package private) static void` `removeTemporaryFiles()` Remove all marked temporary files in the given directory.
`(package private) static java.lang.String` `replace​(java.lang.String s1, java.lang.String s2, java.lang.String str)`
`(package private) static void` `setByte​(Pointer pointer, long baseaddr, long offset, byte value)`
`static void` `setCallbackExceptionHandler​(Callback.UncaughtExceptionHandler eh)` Set the default handler invoked when a callback throws an uncaught exception.
`static void` `setCallbackThreadInitializer​(Callback cb, CallbackThreadInitializer initializer)` Set a thread initializer for the given callback.
`(package private) static void` `setChar​(Pointer pointer, long baseaddr, long offset, char value)`
`(package private) static void` `setDouble​(Pointer pointer, long baseaddr, long offset, double value)`
`(package private) static void` `setFloat​(Pointer pointer, long baseaddr, long offset, float value)`
`(package private) static void` `setInt​(Pointer pointer, long baseaddr, long offset, int value)`
`static void` `setLastError​(int code)` Set the OS last error code.
`(package private) static void` `setLong​(Pointer pointer, long baseaddr, long offset, long value)`
`(package private) static void` `setMemory​(Pointer pointer, long baseaddr, long offset, long length, byte value)`
`(package private) static void` `setPointer​(Pointer pointer, long baseaddr, long offset, long value)`
`static void` `setProtected​(boolean enable)` Set whether native memory accesses are protected from invalid accesses.
`(package private) static void` `setShort​(Pointer pointer, long baseaddr, long offset, short value)`
`(package private) static void` `setWideString​(Pointer pointer, long baseaddr, long offset, java.lang.String value)`
`static Library` `synchronizedLibrary​(Library library)` Returns a synchronized (thread-safe) library backed by the specified library.
`static byte[]` `toByteArray​(java.lang.String s)`
`static byte[]` `toByteArray​(java.lang.String s, java.lang.String encoding)`
`static byte[]` `toByteArray​(java.lang.String s, java.nio.charset.Charset charset)`
`static char[]` `toCharArray​(java.lang.String s)`
`static java.lang.String` `toString​(byte[] buf)` Obtain a Java String from the given native byte array.
`static java.lang.String` `toString​(byte[] buf, java.lang.String encoding)` Obtain a Java String from the given native byte array, using the given encoding.
`static java.lang.String` `toString​(byte[] buf, java.nio.charset.Charset charset)` Obtain a Java String from the given native byte array, using the given encoding.
`static java.lang.String` `toString​(char[] buf)` Obtain a Java String from the given native wchar_t array.
`static java.util.List<java.lang.String>` `toStringList​(char[] buf)` Converts a "list" of strings each null terminated into a `List` of `String` values.
`static java.util.List<java.lang.String>` `toStringList​(char[] buf, int offset, int len)` Converts a "list" of strings each null terminated into a `List` of `String` values.
`static void` `unregister()` Remove all native mappings for the calling class.
`static void` `unregister​(java.lang.Class<?> cls)` Remove all native mappings for the given class.
`(package private) static void` `write​(Pointer pointer, long baseaddr, long offset, byte[] buf, int index, int length)`
`(package private) static void` `write​(Pointer pointer, long baseaddr, long offset, char[] buf, int index, int length)`
`(package private) static void` `write​(Pointer pointer, long baseaddr, long offset, double[] buf, int index, int length)`
`(package private) static void` `write​(Pointer pointer, long baseaddr, long offset, float[] buf, int index, int length)`
`(package private) static void` `write​(Pointer pointer, long baseaddr, long offset, int[] buf, int index, int length)`
`(package private) static void` `write​(Pointer pointer, long baseaddr, long offset, long[] buf, int index, int length)`
`(package private) static void` `write​(Pointer pointer, long baseaddr, long offset, short[] buf, int index, int length)`

### Methods inherited from class java.lang.Object

`clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

### Field Detail

#### DEFAULT_CHARSET

    public static final java.nio.charset.Charset DEFAULT_CHARSET

#### DEFAULT_ENCODING

    public static final java.lang.String DEFAULT_ENCODING

#### DEBUG_LOAD

    public static final boolean DEBUG_LOAD

#### DEBUG_JNA_LOAD

    public static final boolean DEBUG_JNA_LOAD

#### jnidispatchPath

    static java.lang.String jnidispatchPath

#### POINTER_SIZE

    public static final int POINTER_SIZE

The size of a native pointer (`void*`) on the current platform, in bytes.

#### LONG_SIZE

    public static final int LONG_SIZE

Size of a native `long` type, in bytes.

#### WCHAR_SIZE

    public static final int WCHAR_SIZE

Size of a native `wchar_t` type, in bytes.

#### SIZE_T_SIZE

    public static final int SIZE_T_SIZE

Size of a native `size_t` type, in bytes.

#### BOOL_SIZE

    public static final int BOOL_SIZE

Size of a native `bool` type (C99 and later), in bytes.

#### LONG_DOUBLE_SIZE

    public static final int LONG_DOUBLE_SIZE

Size of a native `long double` type (C99 and later), in bytes.

#### MAX_ALIGNMENT

    static final int MAX_ALIGNMENT

#### MAX_PADDING

    static final int MAX_PADDING

#### JNA_TMPLIB_PREFIX

    static final java.lang.String JNA_TMPLIB_PREFIX

See Also:
  Constant Field Values

#### CB_HAS_INITIALIZER

    static final int CB_HAS_INITIALIZER

Indicates whether the callback has an initializer.

See Also:
  Constant Field Values

#### CB_OPTION_DIRECT

    static final int CB_OPTION_DIRECT

Use direct mapping for callback.

See Also:
  Constant Field Values

#### CB_OPTION_IN_DLL

    static final int CB_OPTION_IN_DLL

Return a DLL-resident fucntion pointer.

See Also:
  Constant Field Values

### Method Detail

#### isCompatibleVersion

    static boolean isCompatibleVersion​(java.lang.String expectedVersion,
                                       java.lang.String nativeVersion)

Version string must have the structure <major>.<minor>.<revision> a bugfix change in the native code increments revision, the minor is incremented for backwards compatible changes and the major version is changed for backwards incompatbile changes.

Parameters:
  `expectedVersion` -
  `nativeVersion` -
Returns:
  true if nativeVersion describes a version compatible to expectedVersion

#### deleteLibrary

    static boolean deleteLibrary​(java.io.File lib)

Remove any automatically unpacked native library. This will fail on windows, which disallows removal of any file that is still in use, so an alternative is required in that case. Mark the file that could not be deleted, and attempt to delete any temporaries on next startup. Do NOT force the class loader to unload the native library, since that introduces issues with cleaning up any extant JNA bits (e.g. Memory) which may still need use of the library before shutdown.

#### setProtected

    public static void setProtected​(boolean enable)

Set whether native memory accesses are protected from invalid accesses. This should only be set true when testing or debugging, and should not be considered reliable or robust for applications where JNA native calls are occurring on multiple threads. Protected mode will be automatically set if the system property `jna.protected` has a value of "true" when the JNA library is first loaded.

If not supported by the underlying platform, this setting will have no effect.

NOTE: On platforms which support signals (non-Windows), JNA uses signals to trap errors. This may interfere with the JVM's own use of signals. When protected mode is enabled, you should make use of the jsig library, if available (see Signal Chaining). In short, set the environment variable `LD_PRELOAD` to the path to `libjsig.so` in your JRE lib directory (usually ${java.home}/lib/${os.arch}/libjsig.so) before launching your Java application.

#### isProtected

    public static boolean isProtected()

Returns whether protection is enabled. Check the result of this method after calling `setProtected(true)` to determine if this platform supports protecting memory accesses.

#### getWindowID

    public static long getWindowID​(java.awt.Window w)
                            throws java.awt.HeadlessException

Utility method to get the native window ID for a Java `Window` as a `long` value. This method is primarily for X11-based systems, which use an opaque `XID` (usually `long int`) to identify windows.

Throws:
  `java.awt.HeadlessException` - if the current VM is running headless

#### getComponentID

    public static long getComponentID​(java.awt.Component c)
                               throws java.awt.HeadlessException

Utility method to get the native window ID for a heavyweight Java `Component` as a `long` value. This method is primarily for X11-based systems, which use an opaque `XID` (usually `long int`) to identify windows.

Throws:
  `java.awt.HeadlessException` - if the current VM is running headless

#### getWindowPointer

    public static Pointer getWindowPointer​(java.awt.Window w)
                                    throws java.awt.HeadlessException

Utility method to get the native window pointer for a Java `Window` as a `Pointer` value. This method is primarily for w32, which uses the `HANDLE` type (actually `void *`) to identify windows.

Throws:
  `java.awt.HeadlessException` - if the current VM is running headless

#### getComponentPointer

    public static Pointer getComponentPointer​(java.awt.Component c)
                                       throws java.awt.HeadlessException

Utility method to get the native window pointer for a heavyweight Java `Component` as a `Pointer` value. This method is primarily for w32, which uses the `HWND` type (actually `void *`) to identify windows.

Throws:
  `java.awt.HeadlessException` - if the current VM is running headless

#### getWindowHandle0

    static long getWindowHandle0​(java.awt.Component c)

#### getDirectBufferPointer

    public static Pointer getDirectBufferPointer​(java.nio.Buffer b)

Convert a direct `Buffer` into a `Pointer`.

Throws:
  `java.lang.IllegalArgumentException` - if the buffer is not direct.

#### toString

    public static java.lang.String toString​(byte[] buf)

Obtain a Java String from the given native byte array. If there is no NUL terminator, the String will comprise the entire array. The encoding is obtained from `getDefaultStringEncoding()`.

Parameters:
  `buf` - The buffer containing the encoded bytes
See Also:
  `toString(byte[], String)`

#### toString

    public static java.lang.String toString​(byte[] buf,
                                            java.lang.String encoding)

Obtain a Java String from the given native byte array, using the given encoding. If there is no NUL terminator, the String will comprise the entire array.

Usage note: This function assumes, that `buf` holds a `char` array. This means only single-byte encodings are supported.

Parameters:
  `buf` - The buffer containing the encoded bytes. Must not be `null`.
  `encoding` - The encoding name - if `null` then the platform default encoding will be used

#### toString

    public static java.lang.String toString​(byte[] buf,
                                            java.nio.charset.Charset charset)

Obtain a Java String from the given native byte array, using the given encoding. If there is no NUL terminator, the String will comprise the entire array.

Usage note: This function assumes, that `buf` holds a `char` array. This means only single-byte encodings are supported.

Parameters:
  `buf` - The buffer containing the encoded bytes. Must not be `null`.
  `charset` - The charset to decode `buf`. Must not be `null`.

#### toString

    public static java.lang.String toString​(char[] buf)

Obtain a Java String from the given native wchar_t array. If there is no NUL terminator, the String will comprise the entire array.

Parameters:
  `buf` - The buffer containing the characters

#### toStringList

    public static java.util.List<java.lang.String> toStringList​(char[] buf)

Converts a "list" of strings each null terminated into a `List` of `String` values. The end of the list is signaled by an extra NULL value at the end or by the end of the buffer.

Parameters:
  `buf` - The buffer containing the strings
Returns:
  A `List` of all the strings in the buffer
See Also:
  `toStringList(char[], int, int)`

#### toStringList

    public static java.util.List<java.lang.String> toStringList​(char[] buf,
                                                                int offset,
                                                                int len)

Converts a "list" of strings each null terminated into a `List` of `String` values. The end of the list is signaled by an extra NULL value at the end or by the end of the data.

Parameters:
  `buf` - The buffer containing the strings
  `offset` - Offset to start parsing
  `len` - The total characters to parse
Returns:
  A `List` of all the strings in the buffer

#### load

    public static <T extends Library> T load​(java.lang.Class<T> interfaceClass)

Map a library interface to the current process, providing the explicit interface class. Native libraries loaded via this method may be found in several locations.

Type Parameters:
  `T` - Type of expected wrapper
Parameters:
  `interfaceClass` - The implementation wrapper interface
Returns:
  an instance of the requested interface, mapped to the current process.
Throws:
  `java.lang.UnsatisfiedLinkError` - if the library cannot be found or dependent libraries are missing.

#### load

    public static <T extends Library> T load​(java.lang.Class<T> interfaceClass,
                                             java.util.Map<java.lang.String,​?> options)

Map a library interface to the current process, providing the explicit interface class. Any options provided for the library are cached and associated with the library and any of its defined structures and/or functions. Native libraries loaded via this method may be found in several locations.

Type Parameters:
  `T` - Type of expected wrapper
Parameters:
  `interfaceClass` - The implementation wrapper interface
  `options` - Map of library options
Returns:
  an instance of the requested interface, mapped to the current process.
Throws:
  `java.lang.UnsatisfiedLinkError` - if the library cannot be found or dependent libraries are missing.
See Also:
  `load(String, Class, Map)`

#### load

    public static <T extends Library> T load​(java.lang.String name,
                                             java.lang.Class<T> interfaceClass)

Map a library interface to the given shared library, providing the explicit interface class. If `name` is null, attempts to map onto the current process. Native libraries loaded via this method may be found in several locations.

Type Parameters:
  `T` - Type of expected wrapper
Parameters:
  `name` - Library base name
  `interfaceClass` - The implementation wrapper interface
Returns:
  an instance of the requested interface, mapped to the indicated native library.
Throws:
  `java.lang.UnsatisfiedLinkError` - if the library cannot be found or dependent libraries are missing.
See Also:
  `load(String, Class, Map)`

#### load

    public static <T extends Library> T load​(java.lang.String name,
                                             java.lang.Class<T> interfaceClass,
                                             java.util.Map<java.lang.String,​?> options)

Load a library interface from the given shared library, providing the explicit interface class and a map of options for the library. If no library options are detected the map is interpreted as a map of Java method names to native function names.

If `name` is null, attempts to map onto the current process. Native libraries loaded via this method may be found in several locations.

Type Parameters:
  `T` - Type of expected wrapper
Parameters:
  `name` - Library base name
  `interfaceClass` - The implementation wrapper interface
  `options` - Map of library options
Returns:
  an instance of the requested interface, mapped to the indicated native library.
Throws:
  `java.lang.UnsatisfiedLinkError` - if the library cannot be found or dependent libraries are missing.

#### loadLibrary

    @Deprecated
    public static <T> T loadLibrary​(java.lang.Class<T> interfaceClass)

Deprecated.
Provided for improved compatibility between JNA 4.X and 5.X

See Also:
  `load(java.lang.Class)`

#### loadLibrary

    @Deprecated
    public static <T> T loadLibrary​(java.lang.Class<T> interfaceClass,
                                    java.util.Map<java.lang.String,​?> options)

Deprecated.
Provided for improved compatibility between JNA 4.X and 5.X

See Also:
  `load(java.lang.Class, java.util.Map)`

#### loadLibrary

    @Deprecated
    public static <T> T loadLibrary​(java.lang.String name,
                                    java.lang.Class<T> interfaceClass)

Deprecated.
Provided for improved compatibility between JNA 4.X and 5.X

See Also:
  `load(java.lang.String, java.lang.Class)`

#### loadLibrary

    @Deprecated
    public static <T> T loadLibrary​(java.lang.String name,
                                    java.lang.Class<T> interfaceClass,
                                    java.util.Map<java.lang.String,​?> options)

Deprecated.
Provided for improved compatibility between JNA 4.X and 5.X

See Also:
  `load(java.lang.String, java.lang.Class, java.util.Map)`

#### findEnclosingLibraryClass

    static java.lang.Class<?> findEnclosingLibraryClass​(java.lang.Class<?> cls)

Find the library interface corresponding to the given class. Checks all ancestor classes and interfaces for a declaring class which implements `Library`.

Parameters:
  `cls` - The given class
Returns:
  The enclosing class

#### getLibraryOptions

    public static java.util.Map<java.lang.String,​java.lang.Object> getLibraryOptions​(java.lang.Class<?> type)

Return the preferred native library configuration options for the given class. First attempts to load any field of the interface type within the interface mapping, then checks the cache for any specified library options. If none found, a set of library options will be generated from the fields (by order of precedence) `OPTIONS` (a `Map`), `TYPE_MAPPER` (a `TypeMapper`), `STRUCTURE_ALIGNMENT` (an `Integer`), and `STRING_ENCODING` (a `String`).

Parameters:
  `type` - The type class
Returns:
  The options map

#### getTypeMapper

    public static TypeMapper getTypeMapper​(java.lang.Class<?> cls)

Return the preferred `TypeMapper` for the given native interface. See `Library.OPTION_TYPE_MAPPER`.

#### getStringEncoding

    public static java.lang.String getStringEncoding​(java.lang.Class<?> cls)

Parameters:
  `cls` - The native interface type
Returns:
  The preferred string encoding for the given native interface. If there is no setting, defaults to the `getDefaultStringEncoding()`.
See Also:
  `Library.OPTION_STRING_ENCODING`

#### getDefaultStringEncoding

    public static java.lang.String getDefaultStringEncoding()

Returns:
  The default string encoding. Returns the value of the system property `jna.encoding` or `DEFAULT_ENCODING`.

#### getStructureAlignment

    public static int getStructureAlignment​(java.lang.Class<?> cls)

Parameters:
  `cls` - The native interface type
Returns:
  The preferred structure alignment for the given native interface.
See Also:
  `Library.OPTION_STRUCTURE_ALIGNMENT`

#### getBytes

    static byte[] getBytes​(java.lang.String s)

Parameters:
  `s` - The input string
Returns:
  A byte array corresponding to the given String. The encoding used is obtained from `getDefaultStringEncoding()`.

#### getBytes

    static byte[] getBytes​(java.lang.String s,
                           java.lang.String encoding)

Parameters:
  `s` - The string. Must not be `null`.
  `encoding` - The encoding - if `null` then the default platform encoding is used
Returns:
  A byte array corresponding to the given String, using the given encoding. If the encoding is not found default to the platform native encoding.

#### getBytes

    static byte[] getBytes​(java.lang.String s,
                           java.nio.charset.Charset charset)

Parameters:
  `s` - The string. Must not be `null`.
  `charset` - The charset used to encode `s`. Must not be `null`.
Returns:
  A byte array corresponding to the given String, using the given charset.

#### toByteArray

    public static byte[] toByteArray​(java.lang.String s)

Parameters:
  `s` - The string
Returns:
  A NUL-terminated byte buffer equivalent to the given String, using the encoding returned by `getDefaultStringEncoding()`.
See Also:
  `toByteArray(String, String)`

#### toByteArray

    public static byte[] toByteArray​(java.lang.String s,
                                     java.lang.String encoding)

Parameters:
  `s` - The string. Must not be `null`.
  `encoding` - The encoding - if `null` then the default platform encoding is used
Returns:
  A NUL-terminated byte buffer equivalent to the given String, using the given encoding.
See Also:
  `getBytes(String, String)`

#### toByteArray

    public static byte[] toByteArray​(java.lang.String s,
                                     java.nio.charset.Charset charset)

Parameters:
  `s` - The string. Must not be `null`.
  `charset` - The charset used to encode `s`. Must not be `null`.
Returns:
  A NUL-terminated byte buffer equivalent to the given String, using the given charset.
See Also:
  `getBytes(String, String)`

#### toCharArray

    public static char[] toCharArray​(java.lang.String s)

Parameters:
  `s` - The string
Returns:
  A NUL-terminated wide character buffer equivalent to the given string.

#### isUnpacked

    static boolean isUnpacked​(java.io.File file)

Identify temporary files unpacked from classpath jar files.

#### extractFromResourcePath

    public static java.io.File extractFromResourcePath​(java.lang.String name)
                                                throws java.io.IOException

Attempt to extract a native library from the current resource path, using the current thread context class loader.

Parameters:
  `name` - Base name of native library to extract. May also be an absolute resource path (i.e. starts with "/"), in which case the no transformations of the library name are performed. If only the base name is given, the resource path is attempted both with and without `Platform.RESOURCE_PREFIX`, after mapping the library name via `NativeLibrary.mapSharedLibraryName(String)`.
Returns:
  File indicating extracted resource on disk
Throws:
  `java.io.IOException` - if resource not found

#### extractFromResourcePath

    public static java.io.File extractFromResourcePath​(java.lang.String name,
                                                       java.lang.ClassLoader loader)
                                                throws java.io.IOException

Attempt to extract a native library from the resource path using the given class loader.

Parameters:
  `name` - Base name of native library to extract. May also be an absolute resource path (i.e. starts with "/"), in which case the no transformations of the library name are performed. If only the base name is given, the resource path is attempted both with and without `Platform.RESOURCE_PREFIX`, after mapping the library name via `NativeLibrary.mapSharedLibraryName(String)`.
  `loader` - Class loader to use to load resources
Returns:
  File indicating extracted resource on disk
Throws:
  `java.io.IOException` - if resource not found

#### getLastError

    public static int getLastError()

Retrieve last error set by the OS. This corresponds to `GetLastError()` on Windows, and `errno` on most other platforms. The value is preserved per-thread, but whether the original value is per-thread depends on the underlying OS.

An alternative method of obtaining the last error result is to declare your mapped method to throw `LastErrorException` instead. If a method's signature includes a throw of `LastErrorException`, the last error will be set to zero before the native call and a `LastErrorException` will be raised if the last error value is non-zero after the call, regardless of the actual returned value from the native function.

#### setLastError

    public static void setLastError​(int code)

Set the OS last error code. The value will be saved on a per-thread basis.

#### synchronizedLibrary

    public static Library synchronizedLibrary​(Library library)

Returns a synchronized (thread-safe) library backed by the specified library. This wrapping will prevent simultaneous invocations of any functions mapped to a given `NativeLibrary`. Note that the native library may still be sensitive to being called from different threads.

Parameters:
  `library` - the library to be "wrapped" in a synchronized library.
Returns:
  a synchronized view of the specified library.

#### getWebStartLibraryPath

    public static java.lang.String getWebStartLibraryPath​(java.lang.String libName)

If running web start, determine the location of a given native library. This value may be used to properly set `jna.library.path` so that JNA can load libraries identified by the <nativelib> tag in the JNLP configuration file. Returns `null` if the Web Start native library cache location can not be determined. Note that the path returned may be different for any given library name.

Use `System.getProperty("javawebstart.version")` to detect whether your code is running under Web Start.

Returns:
  null if unable to query the web start loader.
Throws:
  `java.lang.UnsatisfiedLinkError` - if the library can't be found by the Web Start class loader, which usually means it wasn't included as a `<nativelib>` resource in the JNLP file.

#### markTemporaryFile

    static void markTemporaryFile​(java.io.File file)

Perform cleanup of automatically unpacked native shared library.

#### getTempDir

    static java.io.File getTempDir()
                            throws java.io.IOException

Obtain a directory suitable for writing JNA-specific temporary files. Override with `jna.tmpdir`

Throws:
  `java.io.IOException`

#### removeTemporaryFiles

    static void removeTemporaryFiles()
                              throws java.io.IOException

Remove all marked temporary files in the given directory.

Throws:
  `java.io.IOException`

#### getNativeSize

    public static int getNativeSize​(java.lang.Class<?> type,
                                    java.lang.Object value)

Parameters:
  `type` - The Java class for which the native size is to be determined
  `value` - an instance of said class (if available)
Returns:
  the native size of the given class, in bytes. For use with arrays.

#### getNativeSize

    public static int getNativeSize​(java.lang.Class<?> cls)

Returns the native size for a given Java class. Structures are assumed to be `struct` pointers unless they implement `Structure.ByValue`.

Parameters:
  `cls` - The Java class
Returns:
  The native size for the class

#### isSupportedNativeType

    public static boolean isSupportedNativeType​(java.lang.Class<?> cls)

Parameters:
  `cls` - The Java class
Returns:
  `true` whether the given class is supported as a native argument type.

#### setCallbackExceptionHandler

    public static void setCallbackExceptionHandler​(Callback.UncaughtExceptionHandler eh)

Set the default handler invoked when a callback throws an uncaught exception. If the given handler is `null`, the default handler will be reinstated.

Parameters:
  `eh` - The default handler

#### getCallbackExceptionHandler

    public static Callback.UncaughtExceptionHandler getCallbackExceptionHandler()

Returns:
  the current handler for callback uncaught exceptions.

#### register

    public static void register​(java.lang.String libName)

When called from a class static initializer, maps all native methods found within that class to native libraries via the JNA raw calling interface.

Parameters:
  `libName` - library name to which functions should be bound

#### register

    public static void register​(NativeLibrary lib)

When called from a class static initializer, maps all native methods found within that class to native libraries via the JNA raw calling interface.

Parameters:
  `lib` - native library to which functions should be bound

#### findDirectMappedClass

    static java.lang.Class<?> findDirectMappedClass​(java.lang.Class<?> cls)

Find the nearest enclosing class with native methods.

#### getCallingClass

    static java.lang.Class<?> getCallingClass()

Try to determine the class context in which a `register(String)` call was made.

#### setCallbackThreadInitializer

    public static void setCallbackThreadInitializer​(Callback cb,
                                                    CallbackThreadInitializer initializer)

Set a thread initializer for the given callback.

Parameters:
  `cb` - The callback to invoke
  `initializer` - The thread initializer indicates desired thread configuration when the given Callback is invoked on a native thread not yet attached to the VM.

#### unregister

    public static void unregister()

Remove all native mappings for the calling class. Should only be called if the class is no longer referenced and about to be garbage collected.

#### unregister

    public static void unregister​(java.lang.Class<?> cls)

Remove all native mappings for the given class. Should only be called if the class is no longer referenced and about to be garbage collected.

#### registered

    public static boolean registered​(java.lang.Class<?> cls)

Parameters:
  `cls` - The type `Class`
Returns:
  whether the given class's native components are registered.

#### getSignature

    static java.lang.String getSignature​(java.lang.Class<?> cls)

#### replace

    static java.lang.String replace​(java.lang.String s1,
                                    java.lang.String s2,
                                    java.lang.String str)

#### register

    public static void register​(java.lang.Class<?> cls,
                                java.lang.String libName)

When called from a class static initializer, maps all native methods found within that class to native libraries via the JNA raw calling interface. Uses the class loader of the given class to search for the native library in the resource path if it is not found in the system library load path or `jna.library.path`.

Parameters:
  `cls` - Class with native methods to register
  `libName` - name of or path to native library to which functions should be bound

#### register

    public static void register​(java.lang.Class<?> cls,
                                NativeLibrary lib)

When called from a class static initializer, maps all native methods found within that class to native libraries via the JNA raw calling interface.

Parameters:
  `cls` - Class with native methods to register
  `lib` - library to which functions should be bound

#### ffi_prep_cif

    public static long ffi_prep_cif​(int abi,
                                    int nargs,
                                    long ffi_return_type,
                                    long ffi_types)

Create a new cif structure.

#### ffi_call

    public static void ffi_call​(long cif,
                                long fptr,
                                long resp,
                                long args)

Make an FFI function call.

#### ffi_prep_closure

    public static long ffi_prep_closure​(long cif,
                                        Native.ffi_callback cb)

#### ffi_free_closure

    public static void ffi_free_closure​(long closure)

#### initialize_ffi_type

    static int initialize_ffi_type​(long type_info)

Returns the size (calculated by libffi) of the given type.

#### main

    public static void main​(java.lang.String[] args)

Prints JNA library details to the console.

#### freeNativeCallback

    static void freeNativeCallback​(long ptr)

Free the given callback trampoline.

#### createNativeCallback

    static long createNativeCallback​(Callback callback,
                                     java.lang.reflect.Method method,
                                     java.lang.Class<?>[] parameterTypes,
                                     java.lang.Class<?> returnType,
                                     int callingConvention,
                                     int flags,
                                     java.lang.String encoding)

Create a native trampoline to delegate execution to the Java callback.

#### invokeInt

    static int invokeInt​(Function function,
                         long fp,
                         int callFlags,
                         java.lang.Object[] args)

Call the native function.

Parameters:
  `function` - Present to prevent the GC to collect the Function object prematurely
  `fp` - function pointer
  `callFlags` - calling convention to be used
  `args` - Arguments to pass to the native function
Returns:
  The value returned by the target native function

#### invokeLong

    static long invokeLong​(Function function,
                           long fp,
                           int callFlags,
                           java.lang.Object[] args)

Call the native function.

Parameters:
  `function` - Present to prevent the GC to collect the Function object prematurely
  `fp` - function pointer
  `callFlags` - calling convention to be used
  `args` - Arguments to pass to the native function
Returns:
  The value returned by the target native function

#### invokeVoid

    static void invokeVoid​(Function function,
                           long fp,
                           int callFlags,
                           java.lang.Object[] args)

Call the native function.

Parameters:
  `function` - Present to prevent the GC to collect the Function object prematurely
  `fp` - function pointer
  `callFlags` - calling convention to be used
  `args` - Arguments to pass to the native function

#### invokeFloat

    static float invokeFloat​(Function function,
                             long fp,
                             int callFlags,
                             java.lang.Object[] args)

Call the native function.

Parameters:
  `function` - Present to prevent the GC to collect the Function object prematurely
  `fp` - function pointer
  `callFlags` - calling convention to be used
  `args` - Arguments to pass to the native function
Returns:
  The value returned by the target native function

#### invokeDouble

    static double invokeDouble​(Function function,
                               long fp,
                               int callFlags,
                               java.lang.Object[] args)

Call the native function.

Parameters:
  `function` - Present to prevent the GC to collect the Function object prematurely
  `fp` - function pointer
  `callFlags` - calling convention to be used
  `args` - Arguments to pass to the native function
Returns:
  The value returned by the target native function

#### invokePointer

    static long invokePointer​(Function function,
                              long fp,
                              int callFlags,
                              java.lang.Object[] args)

Call the native function.

Parameters:
  `function` - Present to prevent the GC to collect the Function object prematurely
  `fp` - function pointer
  `callFlags` - calling convention to be used
  `args` - Arguments to pass to the native function
Returns:
  The value returned by the target native function

#### invokeStructure

    static Structure invokeStructure​(Function function,
                                     long fp,
                                     int callFlags,
                                     java.lang.Object[] args,
                                     Structure s)

Call the native function, returning a struct by value.

Parameters:
  `function` - Present to prevent the GC to collect the Function object prematurely
  `fp` - function pointer
  `callFlags` - calling convention to be used
  `args` - Arguments to pass to the native function
Returns:
  the passed-in Structure

#### invokeObject

    static java.lang.Object invokeObject​(Function function,
                                         long fp,
                                         int callFlags,
                                         java.lang.Object[] args)

Call the native function, returning a Java `Object`.

Parameters:
  `function` - Present to prevent the GC to collect the Function object prematurely
  `fp` - function pointer
  `callFlags` - calling convention to be used
  `args` - Arguments to pass to the native function
Returns:
  The returned Java `Object`

#### open

    static long open​(java.lang.String name)

Open the requested native library with default options.

#### open

    static long open​(java.lang.String name,
                     int flags)

Open the requested native library with the specified platform-specific otions.

#### close

    static void close​(long handle)

Close the given native library.

#### findSymbol

    static long findSymbol​(long handle,
                           java.lang.String name)

#### indexOf

    static long indexOf​(Pointer pointer,
                        long baseaddr,
                        long offset,
                        byte value)

#### read

    static void read​(Pointer pointer,
                     long baseaddr,
                     long offset,
                     byte[] buf,
                     int index,
                     int length)

#### read

    static void read​(Pointer pointer,
                     long baseaddr,
                     long offset,
                     short[] buf,
                     int index,
                     int length)

#### read

    static void read​(Pointer pointer,
                     long baseaddr,
                     long offset,
                     char[] buf,
                     int index,
                     int length)

#### read

    static void read​(Pointer pointer,
                     long baseaddr,
                     long offset,
                     int[] buf,
                     int index,
                     int length)

#### read

    static void read​(Pointer pointer,
                     long baseaddr,
                     long offset,
                     long[] buf,
                     int index,
                     int length)

#### read

    static void read​(Pointer pointer,
                     long baseaddr,
                     long offset,
                     float[] buf,
                     int index,
                     int length)

#### read

    static void read​(Pointer pointer,
                     long baseaddr,
                     long offset,
                     double[] buf,
                     int index,
                     int length)

#### write

    static void write​(Pointer pointer,
                      long baseaddr,
                      long offset,
                      byte[] buf,
                      int index,
                      int length)

#### write

    static void write​(Pointer pointer,
                      long baseaddr,
                      long offset,
                      short[] buf,
                      int index,
                      int length)

#### write

    static void write​(Pointer pointer,
                      long baseaddr,
                      long offset,
                      char[] buf,
                      int index,
                      int length)

#### write

    static void write​(Pointer pointer,
                      long baseaddr,
                      long offset,
                      int[] buf,
                      int index,
                      int length)

#### write

    static void write​(Pointer pointer,
                      long baseaddr,
                      long offset,
                      long[] buf,
                      int index,
                      int length)

#### write

    static void write​(Pointer pointer,
                      long baseaddr,
                      long offset,
                      float[] buf,
                      int index,
                      int length)

#### write

    static void write​(Pointer pointer,
                      long baseaddr,
                      long offset,
                      double[] buf,
                      int index,
                      int length)

#### getByte

    static byte getByte​(Pointer pointer,
                        long baseaddr,
                        long offset)

#### getChar

    static char getChar​(Pointer pointer,
                        long baseaddr,
                        long offset)

#### getShort

    static short getShort​(Pointer pointer,
                          long baseaddr,
                          long offset)

#### getInt

    static int getInt​(Pointer pointer,
                      long baseaddr,
                      long offset)

#### getLong

    static long getLong​(Pointer pointer,
                        long baseaddr,
                        long offset)

#### getFloat

    static float getFloat​(Pointer pointer,
                          long baseaddr,
                          long offset)

#### getDouble

    static double getDouble​(Pointer pointer,
                            long baseaddr,
                            long offset)

#### getPointer

    static Pointer getPointer​(long addr)

#### getWideString

    static java.lang.String getWideString​(Pointer pointer,
                                          long baseaddr,
                                          long offset)

#### getString

    static java.lang.String getString​(Pointer pointer,
                                      long offset)

#### getString

    static java.lang.String getString​(Pointer pointer,
                                      long offset,
                                      java.lang.String encoding)

#### getStringBytes

    static byte[] getStringBytes​(Pointer pointer,
                                 long baseaddr,
                                 long offset)

#### setMemory

    static void setMemory​(Pointer pointer,
                          long baseaddr,
                          long offset,
                          long length,
                          byte value)

#### setByte

    static void setByte​(Pointer pointer,
                        long baseaddr,
                        long offset,
                        byte value)

#### setShort

    static void setShort​(Pointer pointer,
                         long baseaddr,
                         long offset,
                         short value)

#### setChar

    static void setChar​(Pointer pointer,
                        long baseaddr,
                        long offset,
                        char value)

#### setInt

    static void setInt​(Pointer pointer,
                       long baseaddr,
                       long offset,
                       int value)

#### setLong

    static void setLong​(Pointer pointer,
                        long baseaddr,
                        long offset,
                        long value)

#### setFloat

    static void setFloat​(Pointer pointer,
                         long baseaddr,
                         long offset,
                         float value)

#### setDouble

    static void setDouble​(Pointer pointer,
                          long baseaddr,
                          long offset,
                          double value)

#### setPointer

    static void setPointer​(Pointer pointer,
                           long baseaddr,
                           long offset,
                           long value)

#### setWideString

    static void setWideString​(Pointer pointer,
                              long baseaddr,
                              long offset,
                              java.lang.String value)

#### getDirectByteBuffer

    static java.nio.ByteBuffer getDirectByteBuffer​(Pointer pointer,
                                                   long addr,
                                                   long offset,
                                                   long length)

#### malloc

    public static long malloc​(long size)

Call the real native malloc

Parameters:
  `size` - size of the memory to be allocated
Returns:
  native address of the allocated memory block; zero if the allocation failed.

#### free

    public static void free​(long ptr)

Call the real native free

Parameters:
  `ptr` - native address to be freed; a value of zero has no effect, passing an already-freed pointer will cause pain.

#### detach

    public static void detach​(boolean detach)

Indicate whether the JVM should detach the current native thread when the current Java code finishes execution. Generally this is used to avoid detaching native threads when it is known that a given thread will be relatively long-lived and call back to Java code frequently.

This call is lightweight; it only results in an additional JNI crossing if the desired state changes from its last setting.

Throws:
  `java.lang.IllegalStateException` - if `detach(true)` is called on a thread created by the JVM.

#### getTerminationFlag

    static Pointer getTerminationFlag​(java.lang.Thread t)