org.jpedal.io.RandomAccessDataBuffer Maven / Gradle / Ivy
/*
* ===========================================
* Java Pdf Extraction Decoding Access Library
* ===========================================
*
* Project Info: http://www.idrsolutions.com
* Help section for developers at http://www.idrsolutions.com/support/
*
* (C) Copyright 1997-2017 IDRsolutions and Contributors.
*
* This file is part of JPedal/JPDF2HTML5
*
@LICENSE@
*
* ---------------
* RandomAccessDataBuffer.java
* ---------------
*/
package org.jpedal.io;
import java.io.IOException;
public class RandomAccessDataBuffer implements RandomAccessBuffer {
private byte[] data;
private long pointer;
public RandomAccessDataBuffer(final byte[] data) {
this.data = data;
this.pointer = -1;
}
@Override
public long getFilePointer() throws IOException {
return pointer;
}
@Override
public void seek(final long pos) throws IOException {
if (checkPos(pos)) {
this.pointer = pos;
} else {
throw new IOException("Position out of bounds");
}
}
@Override
public void close() throws IOException {
this.data = null;
this.pointer = -1;
}
@Override
public long length() throws IOException {
if (data != null) {
return data.length;
} else {
throw new IOException("Data buffer not initialized.");
}
}
@Override
public int read() throws IOException {
if (checkPos(this.pointer)) {
return b2i(this.data[(int) pointer++]);
} else {
return -1;
}
}
private int peek() throws IOException {
if (checkPos(this.pointer)) {
return b2i(this.data[(int) pointer]);
} else {
return -1;
}
}
/**
* return next line (returns null if no line)
*/
@Override
public String readLine() throws IOException {
if (this.pointer >= this.data.length - 1) {
return null;
} else {
final StringBuilder buf = new StringBuilder();
int c;
while ((c = read()) >= 0) {
if ((c == 10) || (c == 13)) {
if (((peek() == 10) || (peek() == 13)) && (peek() != c)) {
read();
}
break;
}
buf.append((char) c);
}
return buf.toString();
}
}
@Override
public int read(final byte[] b) throws IOException {
if (data == null) {
throw new IOException("Data buffer not initialized.");
}
if (pointer < 0 || pointer >= data.length) {
return -1;
}
final int length = Math.min(b.length, data.length - (int) pointer);
for (int i = 0; i < length; i++) {
b[i] = data[(int) pointer++];
}
return length;
}
private static int b2i(final byte b) {
if (b >= 0) {
return b;
}
return 256 + b;
}
private boolean checkPos(final long pos) throws IOException {
return ((pos >= 0) && (pos < length()));
}
/* returns the byte data*/
@Override
public byte[] getPdfBuffer() {
return data;
}
}