org.apache.taglibs.standard.lang.jstl.ExpressionString Maven / Gradle / Ivy
/*
* The contents of this file are subject to the terms
* of the Common Development and Distribution License
* (the "License"). You may not use this file except
* in compliance with the License.
*
* You can obtain a copy of the license at
* glassfish/bootstrap/legal/CDDLv1.0.txt or
* https://glassfish.dev.java.net/public/CDDLv1.0.html.
* See the License for the specific language governing
* permissions and limitations under the License.
*
* When distributing Covered Code, include this CDDL
* HEADER in each file and include the License file at
* glassfish/bootstrap/legal/CDDLv1.0.txt. If applicable,
* add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your
* own identifying information: Portions Copyright [yyyy]
* [name of copyright owner]
*
* Copyright 2005 Sun Microsystems, Inc. All rights reserved.
*
* Portions Copyright Apache Software Foundation.
*/
package org.apache.taglibs.standard.lang.jstl;
import java.util.Map;
/**
*
* Represents an expression String consisting of a mixture of
* Strings and Expressions.
*
* @author Nathan Abramson - Art Technology Group
* @author Shawn Bayern
* @version $Change: 181177 $$DateTime: 2001/06/26 08:45:09 $$Author: kchung $
**/
public class ExpressionString
{
//-------------------------------------
// Properties
//-------------------------------------
// property elements
Object [] mElements;
public Object [] getElements ()
{ return mElements; }
public void setElements (Object [] pElements)
{ mElements = pElements; }
//-------------------------------------
/**
*
* Constructor
**/
public ExpressionString (Object [] pElements)
{
mElements = pElements;
}
//-------------------------------------
/**
*
* Evaluates the expression string by evaluating each element,
* converting it to a String (using toString, or "" for null values)
* and concatenating the results into a single String.
**/
public String evaluate (Object pContext,
VariableResolver pResolver,
Map functions,
String defaultPrefix,
Logger pLogger)
throws ELException
{
StringBuffer buf = new StringBuffer ();
for (int i = 0; i < mElements.length; i++) {
Object elem = mElements [i];
if (elem instanceof String) {
buf.append ((String) elem);
}
else if (elem instanceof Expression) {
Object val =
((Expression) elem).evaluate (pContext,
pResolver,
functions,
defaultPrefix,
pLogger);
if (val != null) {
buf.append (val.toString ());
}
}
}
return buf.toString ();
}
//-------------------------------------
/**
*
* Returns the expression in the expression language syntax
**/
public String getExpressionString ()
{
StringBuffer buf = new StringBuffer ();
for (int i = 0; i < mElements.length; i++) {
Object elem = mElements [i];
if (elem instanceof String) {
buf.append ((String) elem);
}
else if (elem instanceof Expression) {
buf.append ("${");
buf.append (((Expression) elem).getExpressionString ());
buf.append ("}");
}
}
return buf.toString ();
}
//-------------------------------------
}