Java example source code file (Runtime.c)

This example Java source code file (Runtime.c) is included in the alvinalexander.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Learn more about this Java project at its project page.

Java - Java tags/keywords

java_java_lang_runtime_freememory, java_java_lang_runtime_maxmemory, java_java_lang_runtime_runfinalization0, java_java_lang_runtime_totalmemory, java_java_lang_runtime_traceinstructions, java_java_lang_runtime_tracemethodcalls, jnicall, jniexport, jvm_activeprocessorcount, jvm_freememory, jvm_gc, jvm_maxmemory, jvm_totalmemory, jvm_tracemethodcalls

The Runtime.c Java example source code

/*
 * Copyright (c) 1994, 2000, 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.
 */

/*
 *      Link foreign methods.  This first half of this file contains the
 *      machine independent dynamic linking routines.
 *      See "BUILD_PLATFORM"/java/lang/linker_md.c to see
 *      the implementation of this shared dynamic linking
 *      interface.
 *
 *      NOTE - source in this file is POSIX.1 compliant, host
 *             specific code lives in the platform specific
 *             code tree.
 */

#include "jni.h"
#include "jni_util.h"
#include "jvm.h"

#include "java_lang_Runtime.h"

JNIEXPORT jlong JNICALL
Java_java_lang_Runtime_freeMemory(JNIEnv *env, jobject this)
{
    return JVM_FreeMemory();
}

JNIEXPORT jlong JNICALL
Java_java_lang_Runtime_totalMemory(JNIEnv *env, jobject this)
{
    return JVM_TotalMemory();
}

JNIEXPORT jlong JNICALL
Java_java_lang_Runtime_maxMemory(JNIEnv *env, jobject this)
{
    return JVM_MaxMemory();
}

JNIEXPORT void JNICALL
Java_java_lang_Runtime_gc(JNIEnv *env, jobject this)
{
    JVM_GC();
}

JNIEXPORT void JNICALL
Java_java_lang_Runtime_traceInstructions(JNIEnv *env, jobject this, jboolean on)
{
    JVM_TraceInstructions(on);
}

JNIEXPORT void JNICALL
Java_java_lang_Runtime_traceMethodCalls(JNIEnv *env, jobject this, jboolean on)
{
    JVM_TraceMethodCalls(on);
}

JNIEXPORT void JNICALL
Java_java_lang_Runtime_runFinalization0(JNIEnv *env, jobject this)
{
    jclass cl;
    jmethodID mid;

    if ((cl = (*env)->FindClass(env, "java/lang/ref/Finalizer"))
        && (mid = (*env)->GetStaticMethodID(env, cl,
                                            "runFinalization", "()V"))) {
        (*env)->CallStaticVoidMethod(env, cl, mid);
    }
}

JNIEXPORT jint JNICALL
Java_java_lang_Runtime_availableProcessors(JNIEnv *env, jobject this)
{
    return JVM_ActiveProcessorCount();
}