/*
* Copyright (C) 2010 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 libcore.java.nio.channels;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.RandomAccessFile;
import java.nio.ByteBuffer;
import java.nio.channels.FileChannel;
import libcore.io.IoUtils;
public class FileChannelTest extends junit.framework.TestCase {
public void testReadOnlyByteArrays() throws Exception {
ByteBuffer readOnly = ByteBuffer.allocate(1).asReadOnlyBuffer();
File tmp = File.createTempFile("FileChannelTest", "tmp");
// You can't read into a read-only buffer...
FileChannel fc = new FileInputStream(tmp).getChannel();
try {
fc.read(readOnly);
fail();
} catch (IllegalArgumentException expected) {
}
try {
fc.read(new ByteBuffer[] { readOnly });
fail();
} catch (IllegalArgumentException expected) {
}
try {
fc.read(new ByteBuffer[] { readOnly }, 0, 1);
fail();
} catch (IllegalArgumentException expected) {
}
try {
fc.read(readOnly, 0L);
fail();
} catch (IllegalArgumentException expected) {
}
fc.close();
// But you can write from a read-only buffer...
fc = new FileOutputStream(tmp).getChannel();
fc.write(readOnly);
fc.write(new ByteBuffer[] { readOnly });
fc.write(new ByteBuffer[] { readOnly }, 0, 1);
fc.write(readOnly, 0L);
fc.close();
}
public void test_readv() throws Exception {
File tmp = File.createTempFile("FileChannelTest", "tmp");
FileChannel fc = new FileOutputStream(tmp).getChannel();
fc.write(ByteBuffer.wrap("abcdABCD".getBytes("US-ASCII")));
fc.close();
// Check that both direct and non-direct buffers work.
fc = new FileInputStream(tmp).getChannel();
ByteBuffer[] buffers = new ByteBuffer[] { ByteBuffer.allocateDirect(4), ByteBuffer.allocate(4) };
assertEquals(8, fc.read(buffers));
fc.close();
assertEquals(8, buffers[0].limit() + buffers[1].limit());
byte[] bytes = new byte[4];
buffers[0].flip();
buffers[0].get(bytes);
assertEquals("abcd", new String(bytes, "US-ASCII"));
buffers[1].flip();
buffers[1].get(bytes);
assertEquals("ABCD", new String(bytes, "US-ASCII"));
}
public void test_writev() throws Exception {
File tmp = File.createTempFile("FileChannelTest", "tmp");
FileChannel fc = new FileOutputStream(tmp).getChannel();
// Check that both direct and non-direct buffers work.
ByteBuffer[] buffers = new ByteBuffer[] { ByteBuffer.allocateDirect(4), ByteBuffer.allocate(4) };
buffers[0].put("abcd".getBytes("US-ASCII")).flip();
buffers[1].put("ABCD".getBytes("US-ASCII")).flip();
assertEquals(8, fc.write(buffers));
fc.close();
assertEquals(8, tmp.length());
assertEquals("abcdABCD", new String(IoUtils.readFileAsString(tmp.getPath())));
}
public void test_append() throws Exception {
File tmp = File.createTempFile("FileChannelTest", "tmp");
FileOutputStream fos = new FileOutputStream(tmp, true);
FileChannel fc = fos.getChannel();
fc.write(ByteBuffer.wrap("hello".getBytes("US-ASCII")));
fc.position(0);
// The RI reports whatever position you set...
assertEquals(0, fc.position());
// ...but writes to the end of the file.
fc.write(ByteBuffer.wrap(" world".getBytes("US-ASCII")));
fos.close();
assertEquals("hello world", new String(IoUtils.readFileAsString(tmp.getPath())));
}
public void test_position_writeAddsPadding() throws Exception {
byte[] initialBytes = "12345".getBytes("US-ASCII");
int initialFileSize = initialBytes.length; // 5
FileChannel fc = createFileContainingBytes(initialBytes);
int positionBeyondSize = 10;
fc.position(positionBeyondSize);
assertEquals(positionBeyondSize, fc.position());
assertEquals(initialFileSize, fc.size());
byte[] newBytes = "6789A".getBytes("US-ASCII");
fc.write(ByteBuffer.wrap(newBytes));
int expectedNewLength = positionBeyondSize + newBytes.length;
assertEquals(expectedNewLength, fc.position());
assertEquals(expectedNewLength, fc.size());
fc.close();
}
public void test_truncate_greaterThanSizeWithPositionChange() throws Exception {
byte[] initialBytes = "12345".getBytes("US-ASCII");
int initialFileSize = initialBytes.length; // 5
FileChannel fc = createFileContainingBytes(initialBytes);
int initialPosition = 40;
fc.position(initialPosition); // Should not affect the file size
assertEquals(initialPosition, fc.position());
assertEquals(initialFileSize, fc.size());
// truncateArg < position, truncateArg > initialFileSize: Should not affect the file size
// and should move the position.
int truncateArg = 10;
fc.truncate(truncateArg); // Should not affect the file size, but should move the position.
assertEquals(initialFileSize, fc.size());
// The RI does not behave properly here, according to the docs for truncate(), position()
// should now be the same as truncateArg.
assertEquals(truncateArg, fc.position());
fc.close();
}
public void test_truncate_greaterThanSizeWithoutPositionChange() throws Exception {
byte[] initialBytes = "123456789A".getBytes("US-ASCII");
int initialFileSize = initialBytes.length; // 10
FileChannel fc = createFileContainingBytes(initialBytes);
int initialPosition = 5;
fc.position(initialPosition);
assertEquals(initialPosition, fc.position());
assertEquals(initialFileSize, fc.size());
// truncateArg > position, truncateArg > initialFileSize: Should not affect the file size
// and should not move the position.
int truncateArg = 15;
fc.truncate(truncateArg);
assertEquals(initialFileSize, fc.size());
assertEquals(initialPosition, fc.position());
fc.close();
}
public void test_truncate_lessThanSizeWithPositionChange() throws Exception {
byte[] initialBytes = "123456789A".getBytes("US-ASCII");
int initialFileSize = initialBytes.length; // 10
FileChannel fc = createFileContainingBytes(initialBytes);
int initialPosition = initialFileSize;
fc.position(initialPosition);
assertEquals(initialPosition, fc.position());
assertEquals(initialFileSize, fc.size());
int truncateArg = 5;
// truncateArg < initialPosition, truncateArg < initialFileSize: Should affect the file size
// and should move the position.
fc.truncate(truncateArg);
assertEquals(truncateArg, fc.size());
assertEquals(truncateArg, fc.position());
fc.close();
}
public void test_truncate_lessThanSizeWithoutPositionChange() throws Exception {
byte[] initialBytes = "123456789A".getBytes("US-ASCII");
int initialFileSize = initialBytes.length; // 10
FileChannel fc = createFileContainingBytes(initialBytes);
int initialPosition = 4;
fc.position(initialPosition);
assertEquals(initialPosition, fc.position());
assertEquals(initialFileSize, fc.size());
int truncateArg = 5;
// truncateArg > initialPosition, truncateArg < initialFileSize: Should affect the file size
// and should not move the position.
fc.truncate(truncateArg);
assertEquals(truncateArg, fc.size());
assertEquals(initialPosition, fc.position());
fc.close();
}
private static FileChannel createFileContainingBytes(byte[] bytes) throws IOException {
File tmp = File.createTempFile("FileChannelTest", "tmp");
FileOutputStream fos = new FileOutputStream(tmp, true);
FileChannel fc = fos.getChannel();
fc.write(ByteBuffer.wrap(bytes));
fc.close();
assertEquals(bytes.length, tmp.length());
fc = new RandomAccessFile(tmp, "rw").getChannel();
assertEquals(bytes.length, fc.size());
return fc;
}
}