/*
* $Id: ResourceTag.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.taglib.bean;
import org.apache.struts.taglib.TagUtils;
import org.apache.struts.util.MessageResources;
import javax.servlet.jsp.JspException;
import javax.servlet.jsp.tagext.TagSupport;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
/**
* Define a scripting variable based on the contents of the specified web
* application resource.
*
* @version $Rev: 471754 $ $Date: 2004-10-16 12:38:42 -0400 (Sat, 16 Oct 2004)
* $
*/
public class ResourceTag extends TagSupport {
// ------------------------------------------------------------- Properties
/**
* Buffer size to use when reading the input stream.
*/
protected static final int BUFFER_SIZE = 256;
/**
* The message resources for this package.
*/
protected static MessageResources messages =
MessageResources.getMessageResources(
"org.apache.struts.taglib.bean.LocalStrings");
/**
* The name of the scripting variable that will be exposed as a page scope
* attribute.
*/
protected String id = null;
/**
* Return an InputStream to the specified resource if this is non-null.
*/
protected String input = null;
/**
* The module-relative URI of the resource whose contents are to be
* exposed.
*/
protected String name = null;
public String getId() {
return (this.id);
}
public void setId(String id) {
this.id = id;
}
public String getInput() {
return (this.input);
}
public void setInput(String input) {
this.input = input;
}
public String getName() {
return (this.name);
}
public void setName(String name) {
this.name = name;
}
// --------------------------------------------------------- Public Methods
/**
* Retrieve the required property and expose it as a scripting variable.
*
* @throws JspException if a JSP exception has occurred
*/
public int doStartTag() throws JspException {
// Acquire an input stream to the specified resource
InputStream stream =
pageContext.getServletContext().getResourceAsStream(name);
if (stream == null) {
JspException e =
new JspException(messages.getMessage("resource.get", name));
TagUtils.getInstance().saveException(pageContext, e);
throw e;
}
// If we are returning an InputStream, do so and return
if (input != null) {
pageContext.setAttribute(id, stream);
return (SKIP_BODY);
}
// Accumulate the contents of this resource into a StringBuffer
try {
StringBuffer sb = new StringBuffer();
InputStreamReader reader = new InputStreamReader(stream);
char[] buffer = new char[BUFFER_SIZE];
int n = 0;
while (true) {
n = reader.read(buffer);
if (n < 1) {
break;
}
sb.append(buffer, 0, n);
}
reader.close();
pageContext.setAttribute(id, sb.toString());
} catch (IOException e) {
TagUtils.getInstance().saveException(pageContext, e);
throw new JspException(messages.getMessage("resource.get", name));
}
return (SKIP_BODY);
}
/**
* Release all allocated resources.
*/
public void release() {
super.release();
id = null;
input = null;
name = null;
}
}