org.apache.taglibs.standard.tag.el.fmt.FormatDateTag Maven / Gradle / Ivy
/*
* Copyright (c) 1997-2018 Oracle and/or its affiliates. All rights reserved.
* Copyright 2004 The Apache Software Foundation
*
* Licensed 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.taglibs.standard.tag.el.fmt;
import java.util.Date;
import javax.servlet.jsp.JspException;
import org.apache.taglibs.standard.lang.support.ExpressionEvaluatorManager;
import org.apache.taglibs.standard.tag.common.fmt.FormatDateSupport;
/**
* A handler for <formatDate> that accepts attributes as Strings
* and evaluates them as expressions at runtime.
*
* @author Jan Luehe
*/
public class FormatDateTag extends FormatDateSupport {
//*********************************************************************
// 'Private' state (implementation details)
private String value_; // stores EL-based property
private String type_; // stores EL-based property
private String dateStyle_; // stores EL-based property
private String timeStyle_; // stores EL-based property
private String pattern_; // stores EL-based property
private String timeZone_; // stores EL-based property
//*********************************************************************
// Constructor
/**
* Constructs a new FormatDateTag. As with TagSupport, subclasses
* should not provide other constructors and are expected to call
* the superclass constructor
*/
public FormatDateTag() {
super();
init();
}
//*********************************************************************
// Tag logic
// evaluates expression and chains to parent
public int doStartTag() throws JspException {
// evaluate any expressions we were passed, once per invocation
evaluateExpressions();
// chain to the parent implementation
return super.doStartTag();
}
// Releases any resources we may have (or inherit)
public void release() {
super.release();
init();
}
//*********************************************************************
// Accessor methods
// for EL-based attribute
public void setValue(String value_) {
this.value_ = value_;
}
// for EL-based attribute
public void setType(String type_) {
this.type_ = type_;
}
// for EL-based attribute
public void setDateStyle(String dateStyle_) {
this.dateStyle_ = dateStyle_;
}
// for EL-based attribute
public void setTimeStyle(String timeStyle_) {
this.timeStyle_ = timeStyle_;
}
// for EL-based attribute
public void setPattern(String pattern_) {
this.pattern_ = pattern_;
}
// for EL-based attribute
public void setTimeZone(String timeZone_) {
this.timeZone_ = timeZone_;
}
//*********************************************************************
// Private (utility) methods
// (re)initializes state (during release() or construction)
private void init() {
// null implies "no expression"
value_ = type_ = dateStyle_ = timeStyle_ = pattern_ = timeZone_ = null;
}
// Evaluates expressions as necessary
private void evaluateExpressions() throws JspException {
/*
* Note: we don't check for type mismatches here; we assume
* the expression evaluator will return the expected type
* (by virtue of knowledge we give it about what that type is).
* A ClassCastException here is truly unexpected, so we let it
* propagate up.
*/
// 'value' attribute (mandatory)
value = (Date) ExpressionEvaluatorManager.evaluate(
"value", value_, Date.class, this, pageContext);
// 'type' attribute
if (type_ != null) {
type = (String) ExpressionEvaluatorManager.evaluate(
"type", type_, String.class, this, pageContext);
}
// 'dateStyle' attribute
if (dateStyle_ != null) {
dateStyle = (String) ExpressionEvaluatorManager.evaluate(
"dateStyle", dateStyle_, String.class, this, pageContext);
}
// 'timeStyle' attribute
if (timeStyle_ != null) {
timeStyle = (String) ExpressionEvaluatorManager.evaluate(
"timeStyle", timeStyle_, String.class, this, pageContext);
}
// 'pattern' attribute
if (pattern_ != null) {
pattern = (String) ExpressionEvaluatorManager.evaluate(
"pattern", pattern_, String.class, this, pageContext);
}
// 'timeZone' attribute
if (timeZone_ != null) {
timeZone = ExpressionEvaluatorManager.evaluate(
"timeZone", timeZone_, Object.class, this, pageContext);
}
}
}