elputtag.java

structs源码

/*
 * $Id: ELPutTag.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.strutsel.taglib.tiles;

import org.apache.struts.tiles.taglib.PutTag;
import org.apache.strutsel.taglib.utils.EvalHelper;

import javax.servlet.jsp.JspException;

/**
 * <p>Put an attribute in enclosing attribute container tag. Enclosing
 * attribute container tag can be : &lt;insert&gt; or &lt;definition&gt;.
 * Exception is thrown if no appropriate tag can be found. Put tag can have
 * following atributes :</p>
 *
 * <ul>
 *
 * <li>name : Name of the attribute</li>
 *
 * <li>value | content : value to put as attribute</li>
 *
 * <li>type : value type. Only valid if value is a String and is set by
 * value="something" or by a bean. Possible type are : string (value is used
 * as direct string), page | template (value is used as a page url to insert),
 * definition (value is used as a definition name to insert)</li>
 *
 * <li>direct : Specify if value is to be used as a direct string or as a page
 * url to insert. This is another way to specify the type. It only apply if
 * value is set as a string, and type is not present.</li>
 *
 * <li>beanName : Name of a bean used for setting value. Only valid if value
 * is not set. If property is specified, value come from bean's property.
 * Otherwise, bean itself is used for value.</li>
 *
 * <li>beanProperty : Name of the property used for retrieving value.</li>
 *
 * <li>beanScope : Scope containing bean. </li>
 *
 * <li>role : Role to check when 'insert' will be called. If enclosing tag is
 * &lt;insert&gt;, role is checked immediately. If enclosing tag is
 * &lt;definition&gt;, role will be checked when this definition will be
 * inserted.</li>
 *
 * </li> Value can also come from tag body. Tag body is taken into account
 * only if value is not set by one of the tag attributes. In this case
 * Attribute type is "string", unless tag body define another type.</li>
 *
 * </ul>
 *
 * <p> This class is a subclass of the class <code>org.apache.struts.taglib.tiles.PutTag</code>
 * which provides most of the described functionality.  This subclass allows
 * all attribute values to be specified as expressions utilizing the
 * JavaServer Pages Standard Library expression language.  </p>
 *
 * @version $Rev: 471754 $
 */
public class ELPutTag extends PutTag {
    /**
     * Instance variable mapped to "name" tag attribute. (Mapping set in
     * associated BeanInfo class.)
     */
    private String nameExpr;

    /**
     * Instance variable mapped to "value" tag attribute. (Mapping set in
     * associated BeanInfo class.)
     */
    private String valueExpr;

    /**
     * Instance variable mapped to "content" tag attribute. (Mapping set in
     * associated BeanInfo class.)
     */
    private String contentExpr;

    /**
     * Instance variable mapped to "direct" tag attribute. (Mapping set in
     * associated BeanInfo class.)
     */
    private String directExpr;

    /**
     * Instance variable mapped to "type" tag attribute. (Mapping set in
     * associated BeanInfo class.)
     */
    private String typeExpr;

    /**
     * Instance variable mapped to "beanName" tag attribute. (Mapping set in
     * associated BeanInfo class.)
     */
    private String beanNameExpr;

    /**
     * Instance variable mapped to "beanProperty" tag attribute. (Mapping set
     * in associated BeanInfo class.)
     */
    private String beanPropertyExpr;

    /**
     * Instance variable mapped to "beanScope" tag attribute. (Mapping set in
     * associated BeanInfo class.)
     */
    private String beanScopeExpr;

    /**
     * Instance variable mapped to "role" tag attribute. (Mapping set in
     * associated BeanInfo class.)
     */
    private String roleExpr;

    /**
     * Getter method for "name" tag attribute. (Mapping set in associated
     * BeanInfo class.)
     */
    public String getNameExpr() {
        return (nameExpr);
    }

    /**
     * Getter method for "value" tag attribute. (Mapping set in associated
     * BeanInfo class.)
     */
    public String getValueExpr() {
        return (valueExpr);
    }

    /**
     * Getter method for "content" tag attribute. (Mapping set in associated
     * BeanInfo class.)
     */
    public String getContentExpr() {
        return (contentExpr);
    }

    /**
     * Getter method for "direct" tag attribute. (Mapping set in associated
     * BeanInfo class.)
     */
    public String getDirectExpr() {
        return (directExpr);
    }

    /**
     * Getter method for "type" tag attribute. (Mapping set in associated
     * BeanInfo class.)
     */
    public String getTypeExpr() {
        return (typeExpr);
    }

    /**
     * Getter method for "beanName" tag attribute. (Mapping set in associated
     * BeanInfo class.)
     */
    public String getBeanNameExpr() {
        return (beanNameExpr);
    }

    /**
     * Getter method for "beanProperty" tag attribute. (Mapping set in
     * associated BeanInfo class.)
     */
    public String getBeanPropertyExpr() {
        return (beanPropertyExpr);
    }

    /**
     * Getter method for "beanScope" tag attribute. (Mapping set in associated
     * BeanInfo class.)
     */
    public String getBeanScopeExpr() {
        return (beanScopeExpr);
    }

    /**
     * Getter method for "role" tag attribute. (Mapping set in associated
     * BeanInfo class.)
     */
    public String getRoleExpr() {
        return (roleExpr);
    }

    /**
     * Setter method for "name" tag attribute. (Mapping set in associated
     * BeanInfo class.)
     */
    public void setNameExpr(String nameExpr) {
        this.nameExpr = nameExpr;
    }

    /**
     * Setter method for "value" tag attribute. (Mapping set in associated
     * BeanInfo class.)
     */
    public void setValueExpr(String valueExpr) {
        this.valueExpr = valueExpr;
    }

    /**
     * Setter method for "content" tag attribute. (Mapping set in associated
     * BeanInfo class.)
     */
    public void setContentExpr(String contentExpr) {
        this.contentExpr = contentExpr;
    }

    /**
     * Setter method for "direct" tag attribute. (Mapping set in associated
     * BeanInfo class.)
     */
    public void setDirectExpr(String directExpr) {
        this.directExpr = directExpr;
    }

    /**
     * Setter method for "type" tag attribute. (Mapping set in associated
     * BeanInfo class.)
     */
    public void setTypeExpr(String typeExpr) {
        this.typeExpr = typeExpr;
    }

    /**
     * Setter method for "beanName" tag attribute. (Mapping set in associated
     * BeanInfo class.)
     */
    public void setBeanNameExpr(String beanNameExpr) {
        this.beanNameExpr = beanNameExpr;
    }

    /**
     * Setter method for "beanProperty" tag attribute. (Mapping set in
     * associated BeanInfo class.)
     */
    public void setBeanPropertyExpr(String beanPropertyExpr) {
        this.beanPropertyExpr = beanPropertyExpr;
    }

    /**
     * Setter method for "beanScope" tag attribute. (Mapping set in associated
     * BeanInfo class.)
     */
    public void setBeanScopeExpr(String beanScopeExpr) {
        this.beanScopeExpr = beanScopeExpr;
    }

    /**
     * Setter method for "role" tag attribute. (Mapping set in associated
     * BeanInfo class.)
     */
    public void setRoleExpr(String roleExpr) {
        this.roleExpr = roleExpr;
    }

    /**
     * Resets attribute values for tag reuse.
     */
    public void release() {
        super.release();
        setNameExpr(null);
        setValueExpr(null);
        setContentExpr(null);
        setDirectExpr(null);
        setTypeExpr(null);
        setBeanNameExpr(null);
        setBeanPropertyExpr(null);
        setBeanScopeExpr(null);
        setRoleExpr(null);
    }

    /**
     * Process the start tag.
     *
     * @throws JspException if a JSP exception has occurred
     */
    public int doStartTag() throws JspException {
        evaluateExpressions();

        return (super.doStartTag());
    }

    /**
     * Processes all attribute values which use the JSTL expression evaluation
     * engine to determine their values.
     *
     * @throws JspException if a JSP exception has occurred
     */
    private void evaluateExpressions()
        throws JspException {
        String string = null;

        if ((string =
                EvalHelper.evalString("name", getNameExpr(), this, pageContext)) != null) {
            setName(string);
        }

        if ((string =
                EvalHelper.evalString("value", getValueExpr(), this, pageContext)) != null) {
            setValue(string);
        }

        if ((string =
                EvalHelper.evalString("content", getContentExpr(), this,
                    pageContext)) != null) {
            setContent(string);
        }

        if ((string =
                EvalHelper.evalString("direct", getDirectExpr(), this,
                    pageContext)) != null) {
            setDirect(string);
        }

        if ((string =
                EvalHelper.evalString("type", getTypeExpr(), this, pageContext)) != null) {
            setType(string);
        }

        if ((string =
                EvalHelper.evalString("beanName", getBeanNameExpr(), this,
                    pageContext)) != null) {
            setBeanName(string);
        }

        if ((string =
                EvalHelper.evalString("beanProperty", getBeanPropertyExpr(),
                    this, pageContext)) != null) {
            setBeanProperty(string);
        }

        if ((string =
                EvalHelper.evalString("beanScope", getBeanScopeExpr(), this,
                    pageContext)) != null) {
            setBeanScope(string);
        }

        if ((string =
                EvalHelper.evalString("role", getRoleExpr(), this, pageContext)) != null) {
            setRole(string);
        }
    }
}