org.apache.tika.parser.wordperfect.WPInputStream 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 org.apache.tika.parser.wordperfect;
import java.io.BufferedInputStream;
import java.io.DataInputStream;
import java.io.EOFException;
import java.io.IOException;
import java.io.InputStream;
import org.apache.commons.lang.StringUtils;
/**
* {@link InputStream} wrapper adding WordPerfect-specific byte-reading methods.
* Applies to both 5.x and 6+ documents.
* @author Pascal Essiembre
*/
class WPInputStream extends InputStream {
private final DataInputStream in;
/**
* Constructor.
* @param in input stream
*/
public WPInputStream(InputStream in) {
if (! in.markSupported()) {
in = new BufferedInputStream(in);
}
this.in = new DataInputStream(in);
}
/**
* Reads a WordPerfect "short": a 2 bytes (16-bit) unsigned value in
* reverse order.
* @return an integer value
* @throws IOException if not enough bytes remain
*/
public int readWPShort() throws IOException {
int ch1 = in.read();
int ch2 = in.read();
if ((ch1 | ch2) < 0) {
throw new EOFException();
}
return (ch2 << 8) + (ch1 << 0);
}
/**
* Reads a WordPerfect "long": a 4 bytes (32-bit) unsigned value in
* reverse order.
* @return a long value
* @throws IOException if not enough bytes remain
*/
public long readWPLong() throws IOException {
int ch1 = in.read();
int ch2 = in.read();
int ch3 = in.read();
int ch4 = in.read();
if ((ch1 | ch2 | ch3 | ch4) < 0) {
throw new EOFException();
}
return ((ch4 << 24) + (ch3 << 16) + (ch2 << 8) + (ch1 << 0));
}
/**
* Reads a WordPerfect byte (8-bit).
* @return byte value
* @throws IOException if not enough bytes remain
*/
public byte readWPByte() throws IOException {
return in.readByte();
}
/**
* Skips the specified number of WordPerfect byte (8-bit).
* @param numOfBytes number of bytes to skip
* @throws IOException if not enough bytes remain
*/
public void skipWPByte(int numOfBytes) throws IOException {
for (int i = 0; i < numOfBytes; i++) {
readWPByte();
}
}
/**
* Reads a WordPerfect character (8-bit).
* @return character
* @throws IOException if not enough bytes remain
*/
public char readWPChar() throws IOException {
int c = in.read();
if (c == -1) {
throw new EOFException();
}
return (char)c;
}
/**
* Reads a WordPerfect string of specified length (1 byte per character).
* @param length how many characters to read
* @return a string
* @throws IOException if not enough bytes remain
*/
public String readWPString(int length) throws IOException {
char[] chars = new char[length];
for (int i = 0; i < length; i++) {
int c = in.read();
if (c == -1) {
throw new EOFException();
}
chars[i] = (char) c;
}
return new String(chars);
}
/**
* Reads a series of bytes of the specified length, converting
* each byte to its hexadecimal representation.
* converting each characters to .
* @param numOfBytes how many byte to read
* @return an hexadecimal string
* @throws IOException if not enough bytes remain
*/
public String readWPHexString(int numOfBytes) throws IOException {
StringBuilder b = new StringBuilder();
for (int i = 0; i < numOfBytes; i++) {
b.append(readWPHex());
}
return b.toString();
}
/**
* Reads the next byte and returns it as an hexadecimal value.
* @return hexadecimal string for a single byte
* @throws IOException if not enough bytes remain
*/
public String readWPHex() throws IOException {
return StringUtils.leftPad(Integer.toString(readWP(), 16), 2, '0');
}
/**
* Reads a byte
* @return byte read
* @throws IOException if not enough bytes remain
*/
public int readWP() throws IOException {
int i = read();
if (i == -1) {
throw new EOFException();
}
return i;
}
@Override
public int read() throws IOException {
return in.read();
}
/**
* Does not guarantee full buffer is read.
*/
@Override
public int read(byte[] b) throws IOException {
return in.read(b);
}
/**
* Does not guarantee full buffer is read.
*/
@Override
public int read(byte[] b, int off, int len) throws IOException {
return in.read(b, off, len);
}
/**
* Does not guarantee full length is skipped.
*/
@Override
public long skip(long n) throws IOException {
return in.skip(n);
}
@Override
public int available() throws IOException {
return in.available();
}
@Override
public void close() throws IOException {
in.close();
}
@Override
public synchronized void mark(int readlimit) {
in.mark(readlimit);
}
@Override
public synchronized void reset() throws IOException {
in.reset();
}
@Override
public boolean markSupported() {
return in.markSupported();
}
}