Struts example source code file (Label.java)

This example Struts source code file (Label.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Struts tags/keywords

html, http, httpservletresponse, label, label, object, object, render, request, response, servlet, string, string, strutstag, strutstagattribute, template, template, uibean

The Struts Label.java source code

/*
 * $Id: Label.java 751799 2009-03-09 19:28:20Z musachy $
 *
 * 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.struts2.components;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.struts2.views.annotations.StrutsTag;
import org.apache.struts2.views.annotations.StrutsTagAttribute;
import org.apache.struts2.util.TextProviderHelper;

import com.opensymphony.xwork2.util.ValueStack;

/**
 * <!-- START SNIPPET: javadoc -->
 * Renders an HTML LABEL that will allow you to output label:name combination that has the same format treatment as
 * the rest of your UI controls.</p>
 * <!-- END SNIPPET: javadoc -->
 *
 * <p/> Examples
 * <p/>
 * <!-- START SNIPPET: exdescription -->
 * In this example, a label is rendered. The label is retrieved from a ResourceBundle via the key attribute
 * giving you an output of 'User Name: Ford.Prefect'. Assuming that i18n message userName corresponds
 * to 'User Name' and the action's getUserName() method returns 'Ford.Prefect'<p/>
 * <!-- END SNIPPET: exdescription -->
 * <pre>
 * <!-- START SNIPPET: example -->
 * <s:label key="userName" />
 * <!-- END SNIPPET: example -->
 * </pre>
 * <pre>
 * <!-- START SNIPPET: example2 -->
 * <s:label name="userName" label="User Name" />
 * <!-- END SNIPPET: example -->
 * </pre>
 *
 */
@StrutsTag(
    name="label",
    tldTagClass="org.apache.struts2.views.jsp.ui.LabelTag",
    description="Render a label that displays read-only information",
    allowDynamicAttributes=true)
public class Label extends UIBean {
    final public static String TEMPLATE = "label";

    protected String forAttr;

    public Label(ValueStack stack, HttpServletRequest request, HttpServletResponse response) {
        super(stack, request, response);
    }

    protected String getDefaultTemplate() {
        return TEMPLATE;
    }

    protected void evaluateExtraParams() {
        super.evaluateExtraParams();

        if (forAttr != null) {
            addParameter("for", findString(forAttr));
        }

        // try value, then key, then name (this overrides the default behavior in the superclass)
        if (value != null) {
            addParameter("nameValue", findString(value));
        } else if (key != null) {
            Object nameValue = parameters.get("nameValue");
            if (nameValue == null || nameValue.toString().length() == 0) {
                // get the label from a TextProvider (default value is the key)
                String providedLabel = TextProviderHelper.getText(key, key, stack);
                addParameter("nameValue", providedLabel);
            }
        } else if (name != null) {
            String expr = completeExpressionIfAltSyntax(name);
            addParameter("nameValue", findString(expr));
        }
    }

    @StrutsTagAttribute(description=" HTML for attribute")
    public void setFor(String forAttr) {
        this.forAttr = forAttr;
    }
}