bundles/common/org.eclipse.apogy.common.lang.java/src/org/eclipse/apogy/common/lang/java/io/LittleEndianDataInputStream.java

/*
 * Copyright (C) 2007, 2018 Google Inc.
 *
 * 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 org.eclipse.apogy.common.lang.java.io;

import java.io.DataInput;
import java.io.DataInputStream;
import java.io.IOException;
import java.io.InputStream;

public class LittleEndianDataInputStream extends InputStream implements DataInput {

	public LittleEndianDataInputStream(InputStream in) {
		this.in = in;
		this.d = new DataInputStream(in);
		this.w = new byte[8];
	}

	@Override
	public int available() throws IOException {
		return this.d.available();
	}

	@Override
	public final short readShort() throws IOException {
		this.d.readFully(this.w, 0, 2);
		return (short) ((this.w[1] & 0xff) << 8 | (this.w[0] & 0xff));
	}

	/**
	 * Note, returns int even though it reads a short.
	 */
	@Override
	public final int readUnsignedShort() throws IOException {
		this.d.readFully(this.w, 0, 2);
		return ((this.w[1] & 0xff) << 8 | (this.w[0] & 0xff));
	}

	/**
	 * like DataInputStream.readChar except little endian.
	 */
	@Override
	public final char readChar() throws IOException {
		this.d.readFully(this.w, 0, 2);
		return (char) ((this.w[1] & 0xff) << 8 | (this.w[0] & 0xff));
	}

	/**
	 * like DataInputStream.readInt except little endian.
	 */
	@Override
	public final int readInt() throws IOException {
		this.d.readFully(this.w, 0, 4);
		return (this.w[3]) << 24 | (this.w[2] & 0xff) << 16 | (this.w[1] & 0xff) << 8 | (this.w[0] & 0xff);
	}

	/**
	 * like DataInputStream.readLong except little endian.
	 */
	@Override
	public final long readLong() throws IOException {
		this.d.readFully(this.w, 0, 8);
		return (long) (this.w[7]) << 56 | (long) (this.w[6] & 0xff) << 48 | (long) (this.w[5] & 0xff) << 40
				| (long) (this.w[4] & 0xff) << 32 | (long) (this.w[3] & 0xff) << 24 | (long) (this.w[2] & 0xff) << 16
				| (long) (this.w[1] & 0xff) << 8 | this.w[0] & 0xff;
	}

	@Override
	public final float readFloat() throws IOException {
		return Float.intBitsToFloat(readInt());
	}

	@Override
	public final double readDouble() throws IOException {
		return Double.longBitsToDouble(readLong());
	}

	@Override
	public final int read(byte b[], int off, int len) throws IOException {
		return this.in.read(b, off, len);
	}

	@Override
	public final void readFully(byte b[]) throws IOException {
		this.d.readFully(b, 0, b.length);
	}

	@Override
	public final void readFully(byte b[], int off, int len) throws IOException {
		this.d.readFully(b, off, len);
	}

	@Override
	public final int skipBytes(int n) throws IOException {
		return this.d.skipBytes(n);
	}

	@Override
	public final boolean readBoolean() throws IOException {
		return this.d.readBoolean();
	}

	@Override
	public final byte readByte() throws IOException {
		return this.d.readByte();
	}

	@Override
	public int read() throws IOException {
		return this.in.read();
	}

	@Override
	public final int readUnsignedByte() throws IOException {
		return this.d.readUnsignedByte();
	}

	@Override
	@Deprecated
	public final String readLine() throws IOException {
		return this.d.readLine();
	}

	@Override
	public final String readUTF() throws IOException {
		return this.d.readUTF();
	}

	@Override
	public final void close() throws IOException {
		this.d.close();
	}

	private final DataInputStream d; // to get at high level readFully methods of
	// DataInputStream
	private final InputStream in; // to get at the low-level read methods of
	// InputStream
	private final byte w[]; // work array for buffering input

	@Override
	public synchronized void reset() throws IOException {
		this.in.reset();
	}

	@Override
	public synchronized void mark(int readlimit) {
		this.in.mark(Integer.MAX_VALUE);
	}

	@Override
	public boolean markSupported() {
		return this.in.markSupported();
	}

}