/*
* NOTE: This copyright does *not* cover user programs that use HQ
* program services by normal system calls through the application
* program interfaces provided as part of the Hyperic Plug-in Development
* Kit or the Hyperic Client Development Kit - this is merely considered
* normal use of the program, and does *not* fall under the heading of
* "derived work".
*
* Copyright (C) [2004, 2005, 2006], Hyperic, Inc.
* This file is part of HQ.
*
* HQ is free software; you can redistribute it and/or modify
* it under the terms version 2 of the GNU General Public License as
* published by the Free Software Foundation. This program is distributed
* in the hope that it will be useful, but WITHOUT ANY WARRANTY; without
* even the implied warranty of MERCHANTABILITY or FITNESS FOR A
* PARTICULAR PURPOSE. See the GNU General Public License for more
* details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
* USA.
*/
package org.hyperic.util.filter;
import java.io.FilterInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.PushbackInputStream;
import java.util.Iterator;
import java.util.Map;
import java.util.Set;
import org.apache.tools.ant.types.FilterSet;
public class TokenReplacerFilterInputStream extends FilterInputStream {
private static final String DEFAULT_TOKEN_BEGIN = "${";
private static final String DEFAULT_TOKEN_END = "}";
private static final int DEFAULT_BUFSIZ = 8192;
private PushbackInputStream is;
private FilterSet filter;
private byte[] buffer; // internal buffer
private int index; // index into our buffer
// Public constructors
public TokenReplacerFilterInputStream(InputStream in) {
super(in);
this.is = new PushbackInputStream(in, DEFAULT_BUFSIZ);
this.buffer = null;
this.index = 0;
this.filter = new FilterSet();
this.filter.setBeginToken(DEFAULT_TOKEN_BEGIN);
this.filter.setEndToken(DEFAULT_TOKEN_END);
}
public TokenReplacerFilterInputStream(InputStream in, Map filters) {
this(in);
addFilters(filters);
}
// Configuration
public void setBeginToken(String token)
{
this.filter.setBeginToken(token);
}
public void setEndToken(String token)
{
this.filter.setEndToken(token);
}
public void addFilter(String name, String value)
{
this.filter.addFilter(name, value);
}
public void addFilters(Map filters)
{
Set keys = filters.keySet();
for (Iterator i = keys.iterator(); i.hasNext();) {
String key = (String)i.next();
this.filter.addFilter(key, filters.get(key).toString());
}
}
// Overridden FilterStream methods
public int read () throws IOException {
synchronized (in) {
if (!refreshBuffer()) {
return -1;
}
return this.buffer[this.index++];
}
}
public int read (byte[] buf, int offset, int len) throws IOException {
if (len > buf.length) {
throw new IllegalArgumentException("buffer not large enough");
}
int i;
synchronized (in) {
for (i = 0; i < len; i++) {
if (!refreshBuffer()) {
return (i == 0) ? -1 : i;
}
buf[offset+i] = this.buffer[this.index++];
}
}
return i;
}
// Private helper methods
/**
* The buffer refresh is called every time a character is read from our
* internal buffer. If our index has hit the end of the buffer, we
* refresh the data, making sure that we dont split the character buffer
* between token boundries.
*/
private boolean refreshBuffer() throws IOException {
if (this.buffer == null || this.index >= this.buffer.length) {
byte[] tmp = new byte[DEFAULT_BUFSIZ];
int size;
if ((size = this.is.read(tmp, 0, DEFAULT_BUFSIZ)) == -1) {
return false;
}
String tmpStr = new String(tmp, 0, size);
// check to ensure we dont have a buffer that spans tags
int lastBeginToken =
tmpStr.lastIndexOf(this.filter.getBeginToken());
if (lastBeginToken != -1) {
// have at least one, see if we also have the end tag
int lastEndToken =
tmpStr.indexOf(this.filter.getEndToken(), lastBeginToken);
if (lastEndToken == -1) {
String toPush = tmpStr.substring(lastBeginToken);
tmpStr = tmpStr.substring(0, lastBeginToken);
this.is.unread(toPush.getBytes());
}
// else, the buffer also contained the end tag
}
// reset
String replaced = this.filter.replaceTokens(tmpStr);
this.buffer = replaced.getBytes();
this.index = 0;
}
return true;
}
}