update/org.eclipse.update.core/src/org/eclipse/update/internal/core/Writer.java

package org.eclipse.update.internal.core;

/*
 * (c) Copyright IBM Corp. 2000, 2001.
 * All Rights Reserved.
 */

import java.io.*;

/**
 * write XML file
 */
public class Writer {

	private PrintWriter w;

	/*
	 * 
	 */
	public Writer(File file, String encoding) throws FileNotFoundException, UnsupportedEncodingException{
		super();

		OutputStream out = new FileOutputStream(file);
		OutputStreamWriter outWriter = new OutputStreamWriter(out, "UTF8"); //$NON-NLS-1$
		BufferedWriter buffWriter = new BufferedWriter(outWriter);
		w = new PrintWriter(buffWriter);
	}

	/*
	 * 
	 */
	public Writer(File file) throws FileNotFoundException{
		super();

		OutputStream out = new FileOutputStream(file);
		OutputStreamWriter outWriter = new OutputStreamWriter(out);
		BufferedWriter buffWriter = new BufferedWriter(outWriter);
		w = new PrintWriter(buffWriter);
	}
	
	/*
	 * 
	 */
	public void write(IWritable element) {
		w.println("<?xml version=\"1.0\" encoding=\"UTF-8\"?>"); //$NON-NLS-1$
		w.println(""); //$NON-NLS-1$
		w.println("<!-- File written by Update manager 2.0 -->"); //$NON-NLS-1$
		w.println("<!-- comments in this file are not preserved -->"); //$NON-NLS-1$
		w.println(""); //$NON-NLS-1$
		 ((IWritable) element).write(0, w);
		close();
	}
	
	/*
	 * 
	 */
	 public void close(){
	 	try{
	 		w.close();
	 	} catch (Exception e){}
	 }

	/*
	 * 
	 */
	private static void appendEscapedChar(StringBuffer buffer, char c) {
		String replacement = getReplacement(c);
		if (replacement != null) {
			buffer.append('&');
			buffer.append(replacement);
			buffer.append(';');
		} else {
			if ((c >= ' ' && c <= 0x7E) || c == '\n' || c == '\r' || c == '\t') {
				buffer.append(c);
			} else {
				buffer.append("&#"); //$NON-NLS-1$
				buffer.append(Integer.toString(c));
				buffer.append(';');
			}
		}
	}

	/*
	 * 
	 */
	public static String xmlSafe(String s) {
		StringBuffer result = new StringBuffer(s.length() + 10);
		for (int i = 0; i < s.length(); ++i)
			appendEscapedChar(result, s.charAt(i));
		return result.toString();
	}
	
	/*
	 * 
	 */
	private static String getReplacement(char c) {
		// Encode special XML characters into the equivalent character references.
		// These five are defined by default for all XML documents.
		switch (c) {
			case '<' :
				return "lt"; //$NON-NLS-1$
			case '>' :
				return "gt"; //$NON-NLS-1$
			case '"' :
				return "quot"; //$NON-NLS-1$
			case '\'' :
				return "apos"; //$NON-NLS-1$
			case '&' :
				return "amp"; //$NON-NLS-1$
		}
		return null;
	}
}