/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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 org.apache.commons.io.input;
import org.junit.Test;
import java.io.EOFException;
import java.io.IOException;
import java.io.InputStream;
import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertFalse;
import static org.junit.Assert.assertTrue;
import static org.junit.Assert.fail;
/**
* JUnit Test Case for {@link NullInputStream}.
*
*/
public class NullInputStreamTest {
@Test
public void testRead() throws Exception {
final int size = 5;
final InputStream input = new TestNullInputStream(size);
for (int i = 0; i < size; i++) {
assertEquals("Check Size [" + i + "]", size - i, input.available());
assertEquals("Check Value [" + i + "]", i, input.read());
}
assertEquals("Available after contents all read", 0, input.available());
// Check availbale is zero after End of file
assertEquals("End of File", -1, input.read());
assertEquals("Available after End of File", 0, input.available());
// Test reading after the end of file
try {
final int result = input.read();
fail("Should have thrown an IOException, byte=[" + result + "]");
} catch (final IOException e) {
assertEquals("Read after end of file", e.getMessage());
}
// Close - should reset
input.close();
assertEquals("Available after close", size, input.available());
}
@Test
public void testReadByteArray() throws Exception {
final byte[] bytes = new byte[10];
final InputStream input = new TestNullInputStream(15);
// Read into array
final int count1 = input.read(bytes);
assertEquals("Read 1", bytes.length, count1);
for (int i = 0; i < count1; i++) {
assertEquals("Check Bytes 1", i, bytes[i]);
}
// Read into array
final int count2 = input.read(bytes);
assertEquals("Read 2", 5, count2);
for (int i = 0; i < count2; i++) {
assertEquals("Check Bytes 2", count1 + i, bytes[i]);
}
// End of File
final int count3 = input.read(bytes);
assertEquals("Read 3 (EOF)", -1, count3);
// Test reading after the end of file
try {
final int count4 = input.read(bytes);
fail("Should have thrown an IOException, byte=[" + count4 + "]");
} catch (final IOException e) {
assertEquals("Read after end of file", e.getMessage());
}
// reset by closing
input.close();
// Read into array using offset & length
final int offset = 2;
final int lth = 4;
final int count5 = input.read(bytes, offset, lth);
assertEquals("Read 5", lth, count5);
for (int i = offset; i < lth; i++) {
assertEquals("Check Bytes 2", i, bytes[i]);
}
}
@Test
public void testEOFException() throws Exception {
final InputStream input = new TestNullInputStream(2, false, true);
assertEquals("Read 1", 0, input.read());
assertEquals("Read 2", 1, input.read());
try {
final int result = input.read();
fail("Should have thrown an EOFException, byte=[" + result + "]");
} catch (final EOFException e) {
// expected
}
input.close();
}
@Test
public void testMarkAndReset() throws Exception {
int position = 0;
final int readlimit = 10;
final InputStream input = new TestNullInputStream(100, true, false);
assertTrue("Mark Should be Supported", input.markSupported());
// No Mark
try {
input.reset();
fail("Read limit exceeded, expected IOException ");
} catch (final IOException e) {
assertEquals("No Mark IOException message",
"No position has been marked",
e.getMessage());
}
for (; position < 3; position++) {
assertEquals("Read Before Mark [" + position +"]", position, input.read());
}
// Mark
input.mark(readlimit);
// Read further
for (int i = 0; i < 3; i++) {
assertEquals("Read After Mark [" + i +"]", position + i, input.read());
}
// Reset
input.reset();
// Read From marked position
for (int i = 0; i < readlimit + 1; i++) {
assertEquals("Read After Reset [" + i +"]", position + i, input.read());
}
// Reset after read limit passed
try {
input.reset();
fail("Read limit exceeded, expected IOException ");
} catch (final IOException e) {
assertEquals("Read limit IOException message",
"Marked position [" + position
+ "] is no longer valid - passed the read limit ["
+ readlimit + "]",
e.getMessage());
}
input.close();
}
@Test
public void testMarkNotSupported() throws Exception {
final InputStream input = new TestNullInputStream(100, false, true);
assertFalse("Mark Should NOT be Supported", input.markSupported());
try {
input.mark(5);
fail("mark() should throw UnsupportedOperationException");
} catch (final UnsupportedOperationException e) {
assertEquals("mark() error message", "Mark not supported", e.getMessage());
}
try {
input.reset();
fail("reset() should throw UnsupportedOperationException");
} catch (final UnsupportedOperationException e) {
assertEquals("reset() error message", "Mark not supported", e.getMessage());
}
input.close();
}
@Test
public void testSkip() throws Exception {
final InputStream input = new TestNullInputStream(10, true, false);
assertEquals("Read 1", 0, input.read());
assertEquals("Read 2", 1, input.read());
assertEquals("Skip 1", 5, input.skip(5));
assertEquals("Read 3", 7, input.read());
assertEquals("Skip 2", 2, input.skip(5)); // only 2 left to skip
assertEquals("Skip 3 (EOF)", -1, input.skip(5)); // End of file
try {
input.skip(5); //
fail("Expected IOException for skipping after end of file");
} catch (final IOException e) {
assertEquals("Skip after EOF IOException message",
"Skip after end of file",
e.getMessage());
}
input.close();
}
// ------------- Test NullInputStream implementation -------------
private static final class TestNullInputStream extends NullInputStream {
public TestNullInputStream(final int size) {
super(size);
}
public TestNullInputStream(final int size, final boolean markSupported, final boolean throwEofException) {
super(size, markSupported, throwEofException);
}
@Override
protected int processByte() {
return (int)getPosition() - 1;
}
@Override
protected void processBytes(final byte[] bytes, final int offset, final int length) {
final int startPos = (int)getPosition() - length;
for (int i = offset; i < length; i++) {
bytes[i] = (byte)(startPos + i);
}
}
}
}