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Java example source code file (MappedByteBuffer.c)
The MappedByteBuffer.c Java example source code/* * Copyright (c) 2001, 2010, 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. */ #include "jni.h" #include "jni_util.h" #include "jvm.h" #include "jlong.h" #include "java_nio_MappedByteBuffer.h" #include <sys/mman.h> #include <stddef.h> #include <stdlib.h> JNIEXPORT jboolean JNICALL Java_java_nio_MappedByteBuffer_isLoaded0(JNIEnv *env, jobject obj, jlong address, jlong len, jint numPages) { jboolean loaded = JNI_TRUE; int result = 0; int i = 0; void *a = (void *) jlong_to_ptr(address); #ifdef __linux__ unsigned char *vec = (unsigned char *)malloc(numPages * sizeof(char)); #else char *vec = (char *)malloc(numPages * sizeof(char)); #endif if (vec == NULL) { JNU_ThrowOutOfMemoryError(env, NULL); return JNI_FALSE; } result = mincore(a, (size_t)len, vec); if (result == -1) { JNU_ThrowIOExceptionWithLastError(env, "mincore failed"); free(vec); return JNI_FALSE; } for (i=0; i<numPages; i++) { if (vec[i] == 0) { loaded = JNI_FALSE; break; } } free(vec); return loaded; } JNIEXPORT void JNICALL Java_java_nio_MappedByteBuffer_load0(JNIEnv *env, jobject obj, jlong address, jlong len) { char *a = (char *)jlong_to_ptr(address); int result = madvise((caddr_t)a, (size_t)len, MADV_WILLNEED); if (result == -1) { JNU_ThrowIOExceptionWithLastError(env, "madvise failed"); } } JNIEXPORT void JNICALL Java_java_nio_MappedByteBuffer_force0(JNIEnv *env, jobject obj, jobject fdo, jlong address, jlong len) { void* a = (void *)jlong_to_ptr(address); int result = msync(a, (size_t)len, MS_SYNC); if (result == -1) { JNU_ThrowIOExceptionWithLastError(env, "msync failed"); } } Other Java examples (source code examples)Here is a short list of links related to this Java MappedByteBuffer.c source code file: |
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