com.signalfx.shaded.apache.commons.io.input.RandomAccessFileInputStream Maven / Gradle / Ivy
/*
* 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 com.signalfx.shaded.apache.commons.io.input;
import java.io.IOException;
import java.io.InputStream;
import java.io.RandomAccessFile;
import java.util.Objects;
import com.signalfx.shaded.apache.commons.io.RandomAccessFileMode;
import com.signalfx.shaded.apache.commons.io.build.AbstractOrigin;
import com.signalfx.shaded.apache.commons.io.build.AbstractStreamBuilder;
/**
* Streams data from a {@link RandomAccessFile} starting at its current position.
*
* To build an instance, see {@link Builder}.
*
* @since 2.8.0
*/
public class RandomAccessFileInputStream extends InputStream {
/**
* Builds a new {@link RandomAccessFileInputStream} instance.
*
* For example:
*
* {@code
* RandomAccessFileInputStream s = RandomAccessFileInputStream.builder()
* .setPath(path)
* .setCloseOnClose(true)
* .get();}
*
*
* @since 2.12.0
*/
public static class Builder extends AbstractStreamBuilder {
private RandomAccessFile randomAccessFile;
private boolean closeOnClose;
/**
* Constructs a new instance.
*
* This builder use the aspects RandomAccessFile or File, and closeOnClose. Only set one of RandomAccessFile or an origin that can be converted to a
* File.
*
*
* If RandomAccessFile is not set, then you must provide an origin that can be converted to a File by this builder, otherwise, this call will throw an
* {@link UnsupportedOperationException}.
*
*
* @return a new instance.
* @throws IllegalStateException if both RandomAccessFile and origin are set.
* @throws UnsupportedOperationException if the origin cannot provide a File.
* @see AbstractOrigin#getFile()
*/
@SuppressWarnings("resource") // Caller closes depending on settings
@Override
public RandomAccessFileInputStream get() throws IOException {
if (randomAccessFile != null) {
if (getOrigin() != null) {
throw new IllegalStateException(String.format("Only set one of RandomAccessFile (%s) or origin (%s)", randomAccessFile, getOrigin()));
}
return new RandomAccessFileInputStream(randomAccessFile, closeOnClose);
}
return new RandomAccessFileInputStream(RandomAccessFileMode.READ_ONLY.create(getOrigin().getFile()), closeOnClose);
}
/**
* Sets whether to close the underlying file when this stream is closed.
*
* @param closeOnClose Whether to close the underlying file when this stream is closed.
* @return this
*/
public Builder setCloseOnClose(final boolean closeOnClose) {
this.closeOnClose = closeOnClose;
return this;
}
/**
* Sets the RandomAccessFile to stream.
*
* @param randomAccessFile the RandomAccessFile to stream.
* @return this
*/
public Builder setRandomAccessFile(final RandomAccessFile randomAccessFile) {
this.randomAccessFile = randomAccessFile;
return this;
}
}
/**
* Constructs a new {@link Builder}.
*
* @return a new {@link Builder}.
* @since 2.12.0
*/
public static Builder builder() {
return new Builder();
}
private final boolean closeOnClose;
private final RandomAccessFile randomAccessFile;
/**
* Constructs a new instance configured to leave the underlying file open when this stream is closed.
*
* @param file The file to stream.
* @deprecated Use {@link #builder()}, {@link Builder}, and {@link Builder#get()}
*/
@Deprecated
public RandomAccessFileInputStream(final RandomAccessFile file) {
this(file, false);
}
/**
* Constructs a new instance.
*
* @param file The file to stream.
* @param closeOnClose Whether to close the underlying file when this stream is closed.
* @deprecated Use {@link #builder()}, {@link Builder}, and {@link Builder#get()}
*/
@Deprecated
public RandomAccessFileInputStream(final RandomAccessFile file, final boolean closeOnClose) {
this.randomAccessFile = Objects.requireNonNull(file, "file");
this.closeOnClose = closeOnClose;
}
/**
* Returns an estimate of the number of bytes that can be read (or skipped over) from this input stream.
*
* If there are more than {@link Integer#MAX_VALUE} bytes available, return {@link Integer#MAX_VALUE}.
*
* @return An estimate of the number of bytes that can be read.
* @throws IOException If an I/O error occurs.
*/
@Override
public int available() throws IOException {
final long avail = availableLong();
if (avail > Integer.MAX_VALUE) {
return Integer.MAX_VALUE;
}
return (int) avail;
}
/**
* Returns the number of bytes that can be read (or skipped over) from this input stream.
*
* @return The number of bytes that can be read.
* @throws IOException If an I/O error occurs.
*/
public long availableLong() throws IOException {
return randomAccessFile.length() - randomAccessFile.getFilePointer();
}
@Override
public void close() throws IOException {
super.close();
if (closeOnClose) {
randomAccessFile.close();
}
}
/**
* Gets the underlying file.
*
* @return the underlying file.
*/
public RandomAccessFile getRandomAccessFile() {
return randomAccessFile;
}
/**
* Returns whether to close the underlying file when this stream is closed.
*
* @return Whether to close the underlying file when this stream is closed.
*/
public boolean isCloseOnClose() {
return closeOnClose;
}
@Override
public int read() throws IOException {
return randomAccessFile.read();
}
@Override
public int read(final byte[] bytes) throws IOException {
return randomAccessFile.read(bytes);
}
@Override
public int read(final byte[] bytes, final int offset, final int length) throws IOException {
return randomAccessFile.read(bytes, offset, length);
}
/**
* Delegates to the underlying file.
*
* @param position See {@link RandomAccessFile#seek(long)}.
* @throws IOException See {@link RandomAccessFile#seek(long)}.
* @see RandomAccessFile#seek(long)
*/
private void seek(final long position) throws IOException {
randomAccessFile.seek(position);
}
@Override
public long skip(final long skipCount) throws IOException {
if (skipCount <= 0) {
return 0;
}
final long filePointer = randomAccessFile.getFilePointer();
final long fileLength = randomAccessFile.length();
if (filePointer >= fileLength) {
return 0;
}
final long targetPos = filePointer + skipCount;
final long newPos = targetPos > fileLength ? fileLength - 1 : targetPos;
if (newPos > 0) {
seek(newPos);
}
return randomAccessFile.getFilePointer() - filePointer;
}
}