ByteBufferUtil.java
/*
* Copyright 2023 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package androidx.benchmark.vmtrace;
import androidx.annotation.NonNull;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.nio.ByteBuffer;
import java.nio.ByteOrder;
import java.nio.MappedByteBuffer;
import java.nio.channels.FileChannel;
class ByteBufferUtil {
private ByteBufferUtil() {
}
@NonNull
public static ByteBuffer mapFile(@NonNull File f, long offset, @NonNull ByteOrder byteOrder)
throws IOException {
FileInputStream dataFile = new FileInputStream(f);
try {
FileChannel fc = dataFile.getChannel();
MappedByteBuffer buffer = fc.map(FileChannel.MapMode.READ_ONLY, offset,
f.length() - offset);
buffer.order(byteOrder);
return buffer;
} finally {
dataFile.close(); // this *also* closes the associated channel, fc
}
}
}