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/*
* Copyright (C) 2014 The Android Open Source Project
* Copyright (c) 1995, 2013, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
package java.lang;
import dalvik.annotation.optimization.FastNative;
import java.io.*;
import java.util.StringTokenizer;
import sun.reflect.CallerSensitive;
import java.lang.ref.FinalizerReference;
import java.util.ArrayList;
import java.util.List;
import dalvik.system.BaseDexClassLoader;
import dalvik.system.VMDebug;
import dalvik.system.VMStack;
import dalvik.system.VMRuntime;
import libcore.io.IoUtils;
import libcore.io.Libcore;
import libcore.util.EmptyArray;
import static android.system.OsConstants._SC_NPROCESSORS_CONF;
/**
* Every Java application has a single instance of class
* Runtime
that allows the application to interface with
* the environment in which the application is running. The current
* runtime can be obtained from the getRuntime
method.
*
* An application cannot create its own instance of this class.
*
* @author unascribed
* @see java.lang.Runtime#getRuntime()
* @since JDK1.0
*/
public class Runtime {
private static Runtime currentRuntime = new Runtime();
/**
* Holds the list of threads to run when the VM terminates
*/
private List shutdownHooks = new ArrayList();
/**
* Reflects whether finalization should be run for all objects
* when the VM terminates.
*/
private static boolean finalizeOnExit;
/**
* Reflects whether we are already shutting down the VM.
*/
private boolean shuttingDown;
/**
* Reflects whether we are tracing method calls.
*/
private boolean tracingMethods;
private static native void nativeExit(int code);
/**
* Returns the runtime object associated with the current Java application.
* Most of the methods of class Runtime
are instance
* methods and must be invoked with respect to the current runtime object.
*
* @return the Runtime
object associated with the current
* Java application.
*/
public static Runtime getRuntime() {
return currentRuntime;
}
/** Don't let anyone else instantiate this class */
private Runtime() {}
/**
* Terminates the currently running Java virtual machine by initiating its
* shutdown sequence. This method never returns normally. The argument
* serves as a status code; by convention, a nonzero status code indicates
* abnormal termination.
*
* The virtual machine's shutdown sequence consists of two phases. In
* the first phase all registered {@link #addShutdownHook shutdown hooks},
* if any, are started in some unspecified order and allowed to run
* concurrently until they finish. In the second phase all uninvoked
* finalizers are run if {@link #runFinalizersOnExit finalization-on-exit}
* has been enabled. Once this is done the virtual machine {@link #halt
* halts}.
*
*
If this method is invoked after the virtual machine has begun its
* shutdown sequence then if shutdown hooks are being run this method will
* block indefinitely. If shutdown hooks have already been run and on-exit
* finalization has been enabled then this method halts the virtual machine
* with the given status code if the status is nonzero; otherwise, it
* blocks indefinitely.
*
*
The {@link System#exit(int) System.exit} method is the
* conventional and convenient means of invoking this method.
*
* @param status
* Termination status. By convention, a nonzero status code
* indicates abnormal termination.
*
* @throws SecurityException
* If a security manager is present and its {@link
* SecurityManager#checkExit checkExit} method does not permit
* exiting with the specified status
*
* @see java.lang.SecurityException
* @see java.lang.SecurityManager#checkExit(int)
* @see #addShutdownHook
* @see #removeShutdownHook
* @see #runFinalizersOnExit
* @see #halt(int)
*/
public void exit(int status) {
// Make sure we don't try this several times
synchronized(this) {
if (!shuttingDown) {
shuttingDown = true;
Thread[] hooks;
synchronized (shutdownHooks) {
// create a copy of the hooks
hooks = new Thread[shutdownHooks.size()];
shutdownHooks.toArray(hooks);
}
// Start all shutdown hooks concurrently
for (Thread hook : hooks) {
hook.start();
}
// Wait for all shutdown hooks to finish
for (Thread hook : hooks) {
try {
hook.join();
} catch (InterruptedException ex) {
// Ignore, since we are at VM shutdown.
}
}
// Ensure finalization on exit, if requested
if (finalizeOnExit) {
runFinalization();
}
// Get out of here finally...
nativeExit(status);
}
}
}
/**
* Registers a new virtual-machine shutdown hook.
*
*
The Java virtual machine shuts down in response to two kinds
* of events:
*
*
*
* - The program exits normally, when the last non-daemon
* thread exits or when the {@link #exit exit} (equivalently,
* {@link System#exit(int) System.exit}) method is invoked, or
*
*
- The virtual machine is terminated in response to a
* user interrupt, such as typing ^C, or a system-wide event,
* such as user logoff or system shutdown.
*
*
*
* A shutdown hook is simply an initialized but unstarted
* thread. When the virtual machine begins its shutdown sequence it will
* start all registered shutdown hooks in some unspecified order and let
* them run concurrently. When all the hooks have finished it will then
* run all uninvoked finalizers if finalization-on-exit has been enabled.
* Finally, the virtual machine will halt. Note that daemon threads will
* continue to run during the shutdown sequence, as will non-daemon threads
* if shutdown was initiated by invoking the {@link #exit exit}
* method.
*
*
Once the shutdown sequence has begun it can be stopped only by
* invoking the {@link #halt halt} method, which forcibly
* terminates the virtual machine.
*
*
Once the shutdown sequence has begun it is impossible to register a
* new shutdown hook or de-register a previously-registered hook.
* Attempting either of these operations will cause an
* {@link IllegalStateException} to be thrown.
*
*
Shutdown hooks run at a delicate time in the life cycle of a virtual
* machine and should therefore be coded defensively. They should, in
* particular, be written to be thread-safe and to avoid deadlocks insofar
* as possible. They should also not rely blindly upon services that may
* have registered their own shutdown hooks and therefore may themselves in
* the process of shutting down. Attempts to use other thread-based
* services such as the AWT event-dispatch thread, for example, may lead to
* deadlocks.
*
*
Shutdown hooks should also finish their work quickly. When a
* program invokes {@link #exit exit} the expectation is
* that the virtual machine will promptly shut down and exit. When the
* virtual machine is terminated due to user logoff or system shutdown the
* underlying operating system may only allow a fixed amount of time in
* which to shut down and exit. It is therefore inadvisable to attempt any
* user interaction or to perform a long-running computation in a shutdown
* hook.
*
*
Uncaught exceptions are handled in shutdown hooks just as in any
* other thread, by invoking the {@link ThreadGroup#uncaughtException
* uncaughtException} method of the thread's {@link
* ThreadGroup} object. The default implementation of this method
* prints the exception's stack trace to {@link System#err} and
* terminates the thread; it does not cause the virtual machine to exit or
* halt.
*
*
In rare circumstances the virtual machine may abort, that is,
* stop running without shutting down cleanly. This occurs when the
* virtual machine is terminated externally, for example with the
* SIGKILL signal on Unix or the TerminateProcess call on
* Microsoft Windows. The virtual machine may also abort if a native
* method goes awry by, for example, corrupting internal data structures or
* attempting to access nonexistent memory. If the virtual machine aborts
* then no guarantee can be made about whether or not any shutdown hooks
* will be run.
*
* @param hook
* An initialized but unstarted {@link Thread} object
*
* @throws IllegalArgumentException
* If the specified hook has already been registered,
* or if it can be determined that the hook is already running or
* has already been run
*
* @throws IllegalStateException
* If the virtual machine is already in the process
* of shutting down
*
* @throws SecurityException
* If a security manager is present and it denies
* {@link RuntimePermission}("shutdownHooks")
*
* @see #removeShutdownHook
* @see #halt(int)
* @see #exit(int)
* @since 1.3
*/
public void addShutdownHook(Thread hook) {
// Sanity checks
if (hook == null) {
throw new NullPointerException("hook == null");
}
if (shuttingDown) {
throw new IllegalStateException("VM already shutting down");
}
if (hook.started) {
throw new IllegalArgumentException("Hook has already been started");
}
synchronized (shutdownHooks) {
if (shutdownHooks.contains(hook)) {
throw new IllegalArgumentException("Hook already registered.");
}
shutdownHooks.add(hook);
}
}
/**
* De-registers a previously-registered virtual-machine shutdown hook.
*
* @param hook the hook to remove
* @return true if the specified hook had previously been
* registered and was successfully de-registered, false
* otherwise.
*
* @throws IllegalStateException
* If the virtual machine is already in the process of shutting
* down
*
* @throws SecurityException
* If a security manager is present and it denies
* {@link RuntimePermission}("shutdownHooks")
*
* @see #addShutdownHook
* @see #exit(int)
* @since 1.3
*/
public boolean removeShutdownHook(Thread hook) {
// Sanity checks
if (hook == null) {
throw new NullPointerException("hook == null");
}
if (shuttingDown) {
throw new IllegalStateException("VM already shutting down");
}
synchronized (shutdownHooks) {
return shutdownHooks.remove(hook);
}
}
/**
* Forcibly terminates the currently running Java virtual machine. This
* method never returns normally.
*
*
This method should be used with extreme caution. Unlike the
* {@link #exit exit} method, this method does not cause shutdown
* hooks to be started and does not run uninvoked finalizers if
* finalization-on-exit has been enabled. If the shutdown sequence has
* already been initiated then this method does not wait for any running
* shutdown hooks or finalizers to finish their work.
*
* @param status
* Termination status. By convention, a nonzero status code
* indicates abnormal termination. If the {@link Runtime#exit
* exit} (equivalently, {@link System#exit(int)
* System.exit}) method has already been invoked then this
* status code will override the status code passed to that method.
*
* @throws SecurityException
* If a security manager is present and its {@link
* SecurityManager#checkExit checkExit} method does not permit
* an exit with the specified status
*
* @see #exit
* @see #addShutdownHook
* @see #removeShutdownHook
* @since 1.3
*/
public void halt(int status) {
nativeExit(status);
}
/**
* Enable or disable finalization on exit; doing so specifies that the
* finalizers of all objects that have finalizers that have not yet been
* automatically invoked are to be run before the Java runtime exits.
* By default, finalization on exit is disabled.
*
*
If there is a security manager,
* its checkExit
method is first called
* with 0 as its argument to ensure the exit is allowed.
* This could result in a SecurityException.
*
* @param value true to enable finalization on exit, false to disable
* @deprecated This method is inherently unsafe. It may result in
* finalizers being called on live objects while other threads are
* concurrently manipulating those objects, resulting in erratic
* behavior or deadlock.
*
* @throws SecurityException
* if a security manager exists and its checkExit
* method doesn't allow the exit.
*
* @see java.lang.Runtime#exit(int)
* @see java.lang.Runtime#gc()
* @see java.lang.SecurityManager#checkExit(int)
* @since JDK1.1
*/
@Deprecated
public static void runFinalizersOnExit(boolean value) {
finalizeOnExit = value;
}
/**
* Executes the specified string command in a separate process.
*
*
This is a convenience method. An invocation of the form
* exec(command)
* behaves in exactly the same way as the invocation
* {@link #exec(String, String[], File) exec}(command, null, null).
*
* @param command a specified system command.
*
* @return A new {@link Process} object for managing the subprocess
*
* @throws SecurityException
* If a security manager exists and its
* {@link SecurityManager#checkExec checkExec}
* method doesn't allow creation of the subprocess
*
* @throws IOException
* If an I/O error occurs
*
* @throws NullPointerException
* If command
is null
*
* @throws IllegalArgumentException
* If command
is empty
*
* @see #exec(String[], String[], File)
* @see ProcessBuilder
*/
public Process exec(String command) throws IOException {
return exec(command, null, null);
}
/**
* Executes the specified string command in a separate process with the
* specified environment.
*
*
This is a convenience method. An invocation of the form
* exec(command, envp)
* behaves in exactly the same way as the invocation
* {@link #exec(String, String[], File) exec}(command, envp, null).
*
* @param command a specified system command.
*
* @param envp array of strings, each element of which
* has environment variable settings in the format
* name=value, or
* null if the subprocess should inherit
* the environment of the current process.
*
* @return A new {@link Process} object for managing the subprocess
*
* @throws SecurityException
* If a security manager exists and its
* {@link SecurityManager#checkExec checkExec}
* method doesn't allow creation of the subprocess
*
* @throws IOException
* If an I/O error occurs
*
* @throws NullPointerException
* If command
is null
,
* or one of the elements of envp
is null
*
* @throws IllegalArgumentException
* If command
is empty
*
* @see #exec(String[], String[], File)
* @see ProcessBuilder
*/
public Process exec(String command, String[] envp) throws IOException {
return exec(command, envp, null);
}
/**
* Executes the specified string command in a separate process with the
* specified environment and working directory.
*
*
This is a convenience method. An invocation of the form
* exec(command, envp, dir)
* behaves in exactly the same way as the invocation
* {@link #exec(String[], String[], File) exec}(cmdarray, envp, dir),
* where cmdarray
is an array of all the tokens in
* command
.
*
*
More precisely, the command
string is broken
* into tokens using a {@link StringTokenizer} created by the call
* new {@link StringTokenizer}(command)
with no
* further modification of the character categories. The tokens
* produced by the tokenizer are then placed in the new string
* array cmdarray
, in the same order.
*
* @param command a specified system command.
*
* @param envp array of strings, each element of which
* has environment variable settings in the format
* name=value, or
* null if the subprocess should inherit
* the environment of the current process.
*
* @param dir the working directory of the subprocess, or
* null if the subprocess should inherit
* the working directory of the current process.
*
* @return A new {@link Process} object for managing the subprocess
*
* @throws SecurityException
* If a security manager exists and its
* {@link SecurityManager#checkExec checkExec}
* method doesn't allow creation of the subprocess
*
* @throws IOException
* If an I/O error occurs
*
* @throws NullPointerException
* If command
is null
,
* or one of the elements of envp
is null
*
* @throws IllegalArgumentException
* If command
is empty
*
* @see ProcessBuilder
* @since 1.3
*/
public Process exec(String command, String[] envp, File dir)
throws IOException {
if (command.length() == 0)
throw new IllegalArgumentException("Empty command");
StringTokenizer st = new StringTokenizer(command);
String[] cmdarray = new String[st.countTokens()];
for (int i = 0; st.hasMoreTokens(); i++)
cmdarray[i] = st.nextToken();
return exec(cmdarray, envp, dir);
}
/**
* Executes the specified command and arguments in a separate process.
*
*
This is a convenience method. An invocation of the form
* exec(cmdarray)
* behaves in exactly the same way as the invocation
* {@link #exec(String[], String[], File) exec}(cmdarray, null, null).
*
* @param cmdarray array containing the command to call and
* its arguments.
*
* @return A new {@link Process} object for managing the subprocess
*
* @throws SecurityException
* If a security manager exists and its
* {@link SecurityManager#checkExec checkExec}
* method doesn't allow creation of the subprocess
*
* @throws IOException
* If an I/O error occurs
*
* @throws NullPointerException
* If cmdarray
is null
,
* or one of the elements of cmdarray
is null
*
* @throws IndexOutOfBoundsException
* If cmdarray
is an empty array
* (has length 0
)
*
* @see ProcessBuilder
*/
public Process exec(String cmdarray[]) throws IOException {
return exec(cmdarray, null, null);
}
/**
* Executes the specified command and arguments in a separate process
* with the specified environment.
*
*
This is a convenience method. An invocation of the form
* exec(cmdarray, envp)
* behaves in exactly the same way as the invocation
* {@link #exec(String[], String[], File) exec}(cmdarray, envp, null).
*
* @param cmdarray array containing the command to call and
* its arguments.
*
* @param envp array of strings, each element of which
* has environment variable settings in the format
* name=value, or
* null if the subprocess should inherit
* the environment of the current process.
*
* @return A new {@link Process} object for managing the subprocess
*
* @throws SecurityException
* If a security manager exists and its
* {@link SecurityManager#checkExec checkExec}
* method doesn't allow creation of the subprocess
*
* @throws IOException
* If an I/O error occurs
*
* @throws NullPointerException
* If cmdarray
is null
,
* or one of the elements of cmdarray
is null
,
* or one of the elements of envp
is null
*
* @throws IndexOutOfBoundsException
* If cmdarray
is an empty array
* (has length 0
)
*
* @see ProcessBuilder
*/
public Process exec(String[] cmdarray, String[] envp) throws IOException {
return exec(cmdarray, envp, null);
}
/**
* Executes the specified command and arguments in a separate process with
* the specified environment and working directory.
*
*
Given an array of strings cmdarray
, representing the
* tokens of a command line, and an array of strings envp
,
* representing "environment" variable settings, this method creates
* a new process in which to execute the specified command.
*
*
This method checks that cmdarray
is a valid operating
* system command. Which commands are valid is system-dependent,
* but at the very least the command must be a non-empty list of
* non-null strings.
*
*
If envp is null, the subprocess inherits the
* environment settings of the current process.
*
*
A minimal set of system dependent environment variables may
* be required to start a process on some operating systems.
* As a result, the subprocess may inherit additional environment variable
* settings beyond those in the specified environment.
*
*
{@link ProcessBuilder#start()} is now the preferred way to
* start a process with a modified environment.
*
*
The working directory of the new subprocess is specified by dir.
* If dir is null, the subprocess inherits the
* current working directory of the current process.
*
*
If a security manager exists, its
* {@link SecurityManager#checkExec checkExec}
* method is invoked with the first component of the array
* cmdarray
as its argument. This may result in a
* {@link SecurityException} being thrown.
*
*
Starting an operating system process is highly system-dependent.
* Among the many things that can go wrong are:
*
* - The operating system program file was not found.
*
- Access to the program file was denied.
*
- The working directory does not exist.
*
*
* In such cases an exception will be thrown. The exact nature
* of the exception is system-dependent, but it will always be a
* subclass of {@link IOException}.
*
*
* @param cmdarray array containing the command to call and
* its arguments.
*
* @param envp array of strings, each element of which
* has environment variable settings in the format
* name=value, or
* null if the subprocess should inherit
* the environment of the current process.
*
* @param dir the working directory of the subprocess, or
* null if the subprocess should inherit
* the working directory of the current process.
*
* @return A new {@link Process} object for managing the subprocess
*
* @throws SecurityException
* If a security manager exists and its
* {@link SecurityManager#checkExec checkExec}
* method doesn't allow creation of the subprocess
*
* @throws IOException
* If an I/O error occurs
*
* @throws NullPointerException
* If cmdarray
is null
,
* or one of the elements of cmdarray
is null
,
* or one of the elements of envp
is null
*
* @throws IndexOutOfBoundsException
* If cmdarray
is an empty array
* (has length 0
)
*
* @see ProcessBuilder
* @since 1.3
*/
public Process exec(String[] cmdarray, String[] envp, File dir)
throws IOException {
return new ProcessBuilder(cmdarray)
.environment(envp)
.directory(dir)
.start();
}
/**
* Returns the number of processors available to the Java virtual machine.
*
*
This value may change during a particular invocation of the virtual
* machine. Applications that are sensitive to the number of available
* processors should therefore occasionally poll this property and adjust
* their resource usage appropriately.
*
* @return the maximum number of processors available to the virtual
* machine; never smaller than one
* @since 1.4
*/
public int availableProcessors() {
return (int) Libcore.os.sysconf(_SC_NPROCESSORS_CONF);
}
/**
* Returns the amount of free memory in the Java Virtual Machine.
* Calling the
* gc
method may result in increasing the value returned
* by freeMemory.
*
* @return an approximation to the total amount of memory currently
* available for future allocated objects, measured in bytes.
*/
@FastNative
public native long freeMemory();
/**
* Returns the total amount of memory in the Java virtual machine.
* The value returned by this method may vary over time, depending on
* the host environment.
*
* Note that the amount of memory required to hold an object of any
* given type may be implementation-dependent.
*
* @return the total amount of memory currently available for current
* and future objects, measured in bytes.
*/
@FastNative
public native long totalMemory();
/**
* Returns the maximum amount of memory that the Java virtual machine will
* attempt to use. If there is no inherent limit then the value {@link
* java.lang.Long#MAX_VALUE} will be returned.
*
* @return the maximum amount of memory that the virtual machine will
* attempt to use, measured in bytes
* @since 1.4
*/
@FastNative
public native long maxMemory();
/**
* Runs the garbage collector.
* Calling this method suggests that the Java virtual machine expend
* effort toward recycling unused objects in order to make the memory
* they currently occupy available for quick reuse. When control
* returns from the method call, the virtual machine has made
* its best effort to recycle all discarded objects.
*
* The name gc
stands for "garbage
* collector". The virtual machine performs this recycling
* process automatically as needed, in a separate thread, even if the
* gc
method is not invoked explicitly.
*
* The method {@link System#gc()} is the conventional and convenient
* means of invoking this method.
*/
public native void gc();
/* Wormhole for calling java.lang.ref.Finalizer.runFinalization */
private static native void runFinalization0();
/**
* Runs the finalization methods of any objects pending finalization.
* Calling this method suggests that the Java virtual machine expend
* effort toward running the finalize
methods of objects
* that have been found to be discarded but whose finalize
* methods have not yet been run. When control returns from the
* method call, the virtual machine has made a best effort to
* complete all outstanding finalizations.
*
* The virtual machine performs the finalization process
* automatically as needed, in a separate thread, if the
* runFinalization
method is not invoked explicitly.
*
* The method {@link System#runFinalization()} is the conventional
* and convenient means of invoking this method.
*
* @see java.lang.Object#finalize()
*/
public void runFinalization() {
VMRuntime.runFinalization(0);
}
/**
* Enables/Disables tracing of instructions.
* If the boolean
argument is true
, this
* method suggests that the Java virtual machine emit debugging
* information for each instruction in the virtual machine as it
* is executed. The format of this information, and the file or other
* output stream to which it is emitted, depends on the host environment.
* The virtual machine may ignore this request if it does not support
* this feature. The destination of the trace output is system
* dependent.
*
* If the boolean
argument is false
, this
* method causes the virtual machine to stop performing the
* detailed instruction trace it is performing.
*
* @param on true
to enable instruction tracing;
* false
to disable this feature.
*/
public void traceInstructions(boolean on) {
}
/**
* Enables/Disables tracing of method calls.
* If the boolean
argument is true
, this
* method suggests that the Java virtual machine emit debugging
* information for each method in the virtual machine as it is
* called. The format of this information, and the file or other output
* stream to which it is emitted, depends on the host environment. The
* virtual machine may ignore this request if it does not support
* this feature.
*
* Calling this method with argument false suggests that the
* virtual machine cease emitting per-call debugging information.
*
* Calling this method on Android Lollipop or later (API level >= 21)
* with {@code true} argument will cause it to throw an
* {@code UnsupportedOperationException}.
*
* @param on true
to enable instruction tracing;
* false
to disable this feature.
*/
public void traceMethodCalls(boolean on) {
if (on != tracingMethods) {
if (on) {
VMDebug.startMethodTracing();
} else {
VMDebug.stopMethodTracing();
}
tracingMethods = on;
}
}
/**
* Loads the native library specified by the filename argument. The filename
* argument must be an absolute path name.
* (for example
* Runtime.getRuntime().load("/home/avh/lib/libX11.so");
).
*
* If the filename argument, when stripped of any platform-specific library
* prefix, path, and file extension, indicates a library whose name is,
* for example, L, and a native library called L is statically linked
* with the VM, then the JNI_OnLoad_L function exported by the library
* is invoked rather than attempting to load a dynamic library.
* A filename matching the argument does not have to exist in the file
* system. See the JNI Specification for more details.
*
* Otherwise, the filename argument is mapped to a native library image in
* an implementation-dependent manner.
*
* First, if there is a security manager, its checkLink
* method is called with the filename
as its argument.
* This may result in a security exception.
*
* This is similar to the method {@link #loadLibrary(String)}, but it
* accepts a general file name as an argument rather than just a library
* name, allowing any file of native code to be loaded.
*
* The method {@link System#load(String)} is the conventional and
* convenient means of invoking this method.
*
* @param filename the file to load.
* @exception SecurityException if a security manager exists and its
* checkLink
method doesn't allow
* loading of the specified dynamic library
* @exception UnsatisfiedLinkError if either the filename is not an
* absolute path name, the native library is not statically
* linked with the VM, or the library cannot be mapped to
* a native library image by the host system.
* @exception NullPointerException if filename
is
* null
* @see java.lang.Runtime#getRuntime()
* @see java.lang.SecurityException
* @see java.lang.SecurityManager#checkLink(java.lang.String)
*/
@CallerSensitive
public void load(String filename) {
load0(VMStack.getStackClass1(), filename);
}
/** Check target sdk, if it's higher than N, we throw an UnsupportedOperationException */
private void checkTargetSdkVersionForLoad(String methodName) {
final int targetSdkVersion = VMRuntime.getRuntime().getTargetSdkVersion();
if (targetSdkVersion > 24) {
throw new UnsupportedOperationException(methodName + " is not supported on SDK " +
targetSdkVersion);
}
}
// Fixes b/25859957 regression. Depending on private methods is bad, mkay.
void load(String absolutePath, ClassLoader loader) {
checkTargetSdkVersionForLoad("java.lang.Runtime#load(String, ClassLoader)");
java.lang.System.logE("java.lang.Runtime#load(String, ClassLoader)" +
" is private and will be removed in a future Android release");
if (absolutePath == null) {
throw new NullPointerException("absolutePath == null");
}
String error = nativeLoad(absolutePath, loader);
if (error != null) {
throw new UnsatisfiedLinkError(error);
}
}
synchronized void load0(Class fromClass, String filename) {
if (!(new File(filename).isAbsolute())) {
throw new UnsatisfiedLinkError(
"Expecting an absolute path of the library: " + filename);
}
if (filename == null) {
throw new NullPointerException("filename == null");
}
String error = nativeLoad(filename, fromClass.getClassLoader());
if (error != null) {
throw new UnsatisfiedLinkError(error);
}
}
/**
* Loads the native library specified by the libname
* argument. The libname
argument must not contain any platform
* specific prefix, file extension or path. If a native library
* called libname
is statically linked with the VM, then the
* JNI_OnLoad_libname
function exported by the library is invoked.
* See the JNI Specification for more details.
*
* Otherwise, the libname argument is loaded from a system library
* location and mapped to a native library image in an implementation-
* dependent manner.
*
* First, if there is a security manager, its checkLink
* method is called with the libname
as its argument.
* This may result in a security exception.
*
* The method {@link System#loadLibrary(String)} is the conventional
* and convenient means of invoking this method. If native
* methods are to be used in the implementation of a class, a standard
* strategy is to put the native code in a library file (call it
* LibFile
) and then to put a static initializer:
*
* static { System.loadLibrary("LibFile"); }
*
* within the class declaration. When the class is loaded and
* initialized, the necessary native code implementation for the native
* methods will then be loaded as well.
*
* If this method is called more than once with the same library
* name, the second and subsequent calls are ignored.
*
* @param libname the name of the library.
* @exception SecurityException if a security manager exists and its
* checkLink
method doesn't allow
* loading of the specified dynamic library
* @exception UnsatisfiedLinkError if either the libname argument
* contains a file path, the native library is not statically
* linked with the VM, or the library cannot be mapped to a
* native library image by the host system.
* @exception NullPointerException if libname
is
* null
* @see java.lang.SecurityException
* @see java.lang.SecurityManager#checkLink(java.lang.String)
*/
@CallerSensitive
public void loadLibrary(String libname) {
loadLibrary0(VMStack.getCallingClassLoader(), libname);
}
/**
* Temporarily preserved for backward compatibility. Applications call this
* method using reflection.
*
* **** THIS METHOD WILL BE REMOVED IN A FUTURE ANDROID VERSION ****
*
* http://b/26217329
*
* @hide
*/
public void loadLibrary(String libname, ClassLoader classLoader) {
checkTargetSdkVersionForLoad("java.lang.Runtime#loadLibrary(String, ClassLoader)");
java.lang.System.logE("java.lang.Runtime#loadLibrary(String, ClassLoader)" +
" is private and will be removed in a future Android release");
loadLibrary0(classLoader, libname);
}
synchronized void loadLibrary0(ClassLoader loader, String libname) {
if (libname.indexOf((int)File.separatorChar) != -1) {
throw new UnsatisfiedLinkError(
"Directory separator should not appear in library name: " + libname);
}
String libraryName = libname;
if (loader != null) {
String filename = loader.findLibrary(libraryName);
if (filename == null) {
// It's not necessarily true that the ClassLoader used
// System.mapLibraryName, but the default setup does, and it's
// misleading to say we didn't find "libMyLibrary.so" when we
// actually searched for "liblibMyLibrary.so.so".
throw new UnsatisfiedLinkError(loader + " couldn't find \"" +
System.mapLibraryName(libraryName) + "\"");
}
String error = nativeLoad(filename, loader);
if (error != null) {
throw new UnsatisfiedLinkError(error);
}
return;
}
String filename = System.mapLibraryName(libraryName);
List candidates = new ArrayList();
String lastError = null;
for (String directory : getLibPaths()) {
String candidate = directory + filename;
candidates.add(candidate);
if (IoUtils.canOpenReadOnly(candidate)) {
String error = nativeLoad(candidate, loader);
if (error == null) {
return; // We successfully loaded the library. Job done.
}
lastError = error;
}
}
if (lastError != null) {
throw new UnsatisfiedLinkError(lastError);
}
throw new UnsatisfiedLinkError("Library " + libraryName + " not found; tried " + candidates);
}
private volatile String[] mLibPaths = null;
private String[] getLibPaths() {
if (mLibPaths == null) {
synchronized(this) {
if (mLibPaths == null) {
mLibPaths = initLibPaths();
}
}
}
return mLibPaths;
}
private static String[] initLibPaths() {
String javaLibraryPath = System.getProperty("java.library.path");
if (javaLibraryPath == null) {
return EmptyArray.STRING;
}
String[] paths = javaLibraryPath.split(":");
// Add a '/' to the end of each directory so we don't have to do it every time.
for (int i = 0; i < paths.length; ++i) {
if (!paths[i].endsWith("/")) {
paths[i] += "/";
}
}
return paths;
}
private static native String nativeLoad(String filename, ClassLoader loader);
/**
* Creates a localized version of an input stream. This method takes
* an InputStream
and returns an InputStream
* equivalent to the argument in all respects except that it is
* localized: as characters in the local character set are read from
* the stream, they are automatically converted from the local
* character set to Unicode.
*
* If the argument is already a localized stream, it may be returned
* as the result.
*
* @param in InputStream to localize
* @return a localized input stream
* @see java.io.InputStream
* @see java.io.BufferedReader#BufferedReader(java.io.Reader)
* @see java.io.InputStreamReader#InputStreamReader(java.io.InputStream)
* @deprecated As of JDK 1.1, the preferred way to translate a byte
* stream in the local encoding into a character stream in Unicode is via
* the InputStreamReader
and BufferedReader
* classes.
*/
@Deprecated
public InputStream getLocalizedInputStream(InputStream in) {
return in;
}
/**
* Creates a localized version of an output stream. This method
* takes an OutputStream
and returns an
* OutputStream
equivalent to the argument in all respects
* except that it is localized: as Unicode characters are written to
* the stream, they are automatically converted to the local
* character set.
*
* If the argument is already a localized stream, it may be returned
* as the result.
*
* @deprecated As of JDK 1.1, the preferred way to translate a
* Unicode character stream into a byte stream in the local encoding is via
* the OutputStreamWriter
, BufferedWriter
, and
* PrintWriter
classes.
*
* @param out OutputStream to localize
* @return a localized output stream
* @see java.io.OutputStream
* @see java.io.BufferedWriter#BufferedWriter(java.io.Writer)
* @see java.io.OutputStreamWriter#OutputStreamWriter(java.io.OutputStream)
* @see java.io.PrintWriter#PrintWriter(java.io.OutputStream)
*/
@Deprecated
public OutputStream getLocalizedOutputStream(OutputStream out) {
return out;
}
}