/*******************************************************************************
* Copyright (c) 2007, 2015 Wind River Systems and others.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* Wind River Systems - initial API and implementation
*******************************************************************************/
package org.eclipse.cdt.dsf.debug.internal.ui.disassembly.text;
import java.io.IOException;
/**
* A piece of text on a scratch file.
*/
public class REDRun implements CharSequence {
IFileRider fRider;
int fOffset;
int fLength;
/**
* @pre rider != null
* @pre style != null
* @pre length > 0
*/
public REDRun(IFileRider rider, int offset, int length) {
fRider = rider;
fOffset = offset;
fLength = length;
}
/**
* @pre rider != null
* @pre style != null
* @pre !str.isEmpty()
*/
public REDRun(IFileRider rider, String str) throws IOException {
fRider = rider;
fLength = str.length();
fOffset = fRider.length();
fRider.seek(fOffset);
fRider.writeChars(str, 0, fLength);
}
/**
* @param rider
* @param buf
* @param off
* @param n
*/
public REDRun(IFileRider rider, char[] buf, int off, int n) throws IOException {
fRider = rider;
fLength = n;
fOffset = fRider.length();
fRider.seek(fOffset);
fRider.writeChars(buf, off, n);
}
/**
* @post return.length() == length()
*/
public String asString() throws IOException {
String retVal;
char[] buf = new char[fLength];
fRider.seek(fOffset);
fRider.readChars(buf);
retVal = new String(buf);
return retVal;
}
/**
* Copy parts of run into char-array
* @param arr array to copy into
* @param from offset of arr to copy bytes to
* @param arrSize max offset of arr to write into
* @param myOff offset of run to start reading at
* @return the number of bytes copied
*/
public int copyInto(char[] arr, int from, int arrSize, int myOff) throws IOException {
fRider.seek(fOffset + myOff);
int readAmount = Math.min(arrSize - from, fLength - myOff);
fRider.readChars(arr, from, readAmount);
return readAmount;
}
/**
* Append parts of run to a StringBuffer
* @param buffer StringBuffer to append to
* @param length number of characters to append
* @param myOff offset of run to start reading at
* @return the number of bytes appended
*/
public int appendTo(StringBuffer buffer, int length, int myOff) throws IOException {
fRider.seek(fOffset + myOff);
int readAmount = Math.min(length, fLength - myOff);
fRider.readChars(buffer, readAmount);
return readAmount;
}
/**
* A run is mergable with another if the other a direct successor in the scratch file.
* @pre r != null
*/
public boolean isMergeableWith(REDRun r) {
return r.fRider == fRider && r.fOffset == fOffset + fLength;
}
/*
* @see java.lang.Object#toString()
*/
@Override
public String toString() {
try {
return asString();
} catch (IOException e) {
return ""; //$NON-NLS-1$
}
}
/*
* @see java.lang.CharSequence#charAt(int)
*/
@Override
public char charAt(int pos) {
try {
fRider.seek(fOffset + pos);
return fRider.readChar();
} catch (IOException e) {
return 0;
}
}
/*
* @see java.lang.CharSequence#subSequence(int, int)
*/
@Override
public CharSequence subSequence(int start, int end) {
return new REDRun(fRider, fOffset + start, end - start);
}
/*
* @see java.lang.CharSequence#length()
*/
@Override
public int length() {
return fLength;
}
}