/*
* $Id: ServletContextWriter.java 471754 2006-11-06 14:55:09Z husted $
*
* 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.struts.util;
import javax.servlet.ServletContext;
import java.io.PrintWriter;
import java.io.StringWriter;
/**
* A PrintWriter implementation that uses the logging facilities of a
* <code>javax.servlet.ServletContext</code> to output its results. Output
* will be buffered until a newline character is output, <code>flush()</code>
* is called, or until one of the <code>println()</code> methods is called.
* Along the way, carriage return characters are skipped.
*
* @version $Rev: 471754 $ $Date: 2005-05-07 12:11:38 -0400 (Sat, 07 May 2005)
* $
*/
public class ServletContextWriter extends PrintWriter {
// ------------------------------------------------------------- Properties
/**
* The buffer into which we accumulate lines to be logged.
*/
protected StringBuffer buffer = new StringBuffer();
/**
* The servlet context with which we are associated.
*/
protected ServletContext context = null;
/**
* The error state for this stream.
*/
protected boolean error = false;
// ----------------------------------------------------------- Constructors
/**
* Construct a ServletContextWriter associated with the specified
* ServletContext instance.
*
* @param context The associated servlet context
*/
public ServletContextWriter(ServletContext context) {
super(new StringWriter());
this.context = context;
}
// --------------------------------------------------------- Public Methods
/**
* Flush the stream and check for its error state. <strong>IMPLEMENTATION
* NOTE</strong> - our associated servlet context gives no indication of
* problems with logging, so the only way this method will return
* <code>true</code> is if <code>setError()</code> is called.
*/
public boolean checkError() {
flush();
return (error);
}
/**
* Close the stream.
*/
public void close() {
flush();
}
/**
* Flush the stream.
*/
public void flush() {
if (buffer.length() > 0) {
context.log(buffer.toString());
buffer.setLength(0);
}
}
/**
* Print a boolean value.
*
* @param b The value to be printed
*/
public void print(boolean b) {
write(String.valueOf(b));
}
/**
* Print a character value.
*
* @param c The value to be printed
*/
public void print(char c) {
write(c);
}
/**
* Print a character array.
*
* @param c The character array to be printed
*/
public void print(char[] c) {
for (int i = 0; i < c.length; i++) {
write(c[i]);
}
}
/**
* Print a double value.
*
* @param d The value to be printed
*/
public void print(double d) {
write(String.valueOf(d));
}
/**
* Print a float value.
*
* @param f The value to be printed
*/
public void print(float f) {
write(String.valueOf(f));
}
/**
* Print an integer value.
*
* @param i The value to be printed
*/
public void print(int i) {
write(String.valueOf(i));
}
/**
* Print a long value.
*
* @param l The value to be printed
*/
public void print(long l) {
write(String.valueOf(l));
}
/**
* Print an object.
*
* @param o The value to be printed
*/
public void print(Object o) {
write(o.toString());
}
/**
* Print a String value.
*
* @param s The value to be printed
*/
public void print(String s) {
int len = s.length();
for (int i = 0; i < len; i++) {
write(s.charAt(i));
}
}
/**
* Terminate the current line and flush the buffer.
*/
public void println() {
flush();
}
/**
* Print a boolean value and terminate the line.
*
* @param b The value to be printed
*/
public void println(boolean b) {
println(String.valueOf(b));
}
/**
* Print a character value and terminate the line.
*
* @param c The value to be printed
*/
public void println(char c) {
write(c);
println();
}
/**
* Print a character array and terminate the line.
*
* @param c The character array to be printed
*/
public void println(char[] c) {
for (int i = 0; i < c.length; i++) {
print(c[i]);
}
println();
}
/**
* Print a double value and terminate the line.
*
* @param d The value to be printed
*/
public void println(double d) {
println(String.valueOf(d));
}
/**
* Print a float value and terminate the line.
*
* @param f The value to be printed
*/
public void println(float f) {
println(String.valueOf(f));
}
/**
* Print an integer value and terminate the line.
*
* @param i The value to be printed
*/
public void println(int i) {
println(String.valueOf(i));
}
/**
* Print a long value and terminate the line.
*
* @param l The value to be printed
*/
public void println(long l) {
println(String.valueOf(l));
}
/**
* Print an object and terminate the line.
*
* @param o The value to be printed
*/
public void println(Object o) {
println(o.toString());
}
/**
* Print a String value and terminate the line.
*
* @param s The value to be printed
*/
public void println(String s) {
int len = s.length();
for (int i = 0; i < len; i++) {
print(s.charAt(i));
}
println();
}
/**
* Set the error state for this stream.
*/
public void setError() {
this.error = true;
}
/**
* Write a single character to this stream.
*
* @param c The character to be written
*/
public void write(char c) {
if (c == '\n') {
flush();
} else if (c != '\r') {
buffer.append(c);
}
}
/**
* Write a single character to this stream.
*
* @param c The character to be written
*/
public void write(int c) {
write((char) c);
}
/**
* Write an array of charaters to this stream.
*
* @param buf The character array to be written
*/
public void write(char[] buf) {
for (int i = 0; i < buf.length; i++) {
write(buf[i]);
}
}
/**
* Write the specified subset of an array of characters to this stream.
*
* @param buf The character array from which to write
* @param off The zero-relative starting offset to write
* @param len The number of characters to write
*/
public void write(char[] buf, int off, int len) {
for (int i = off; i < len; i++) {
write(buf[i]);
}
}
/**
* Write a String to this stream.
*
* @param s The string to be written
*/
public void write(String s) {
int len = s.length();
for (int i = 0; i < len; i++) {
write(s.charAt(i));
}
}
/**
* Write the specified portion of a String to this stream.
*
* @param s The String from which to write
* @param off The zero-relative starting offset to write
* @param len The number of characters to write
*/
public void write(String s, int off, int len) {
for (int i = off; i < len; i++) {
write(s.charAt(i));
}
}
}