staticparametersinterceptor.java

在Struts2中的jar包xwork的源代码.版本为2.0.7

/*
 * Copyright (c) 2002-2006 by OpenSymphony
 * All rights reserved.
 */
package com.opensymphony.xwork2.interceptor;

import com.opensymphony.xwork2.ActionContext;
import com.opensymphony.xwork2.ActionInvocation;
import com.opensymphony.xwork2.config.entities.ActionConfig;
import com.opensymphony.xwork2.config.entities.Parameterizable;
import com.opensymphony.xwork2.util.TextParseUtil;
import com.opensymphony.xwork2.util.ValueStack;

import java.util.Iterator;
import java.util.Map;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;


/**
 * <!-- START SNIPPET: description -->
 *
 * This interceptor populates the action with the static parameters defined in the action configuration. If the action
 * implements {@link Parameterizable}, a map of the static parameters will be also be passed directly to the action.
 *
 * <p/> Parameters are typically defined with &lt;param&gt; elements within xwork.xml.
 *
 * <!-- END SNIPPET: description -->
 *
 * <p/> <u>Interceptor parameters:</u>
 *
 * <!-- START SNIPPET: parameters -->
 *
 * <ul>
 *
 * <li>None</li>
 *
 * </ul>
 *
 * <!-- END SNIPPET: parameters -->
 *
 * <p/> <u>Extending the interceptor:</u>
 *
 * <!-- START SNIPPET: extending -->
 *
 * <p/>There are no extension points to this interceptor.
 *
 * <!-- END SNIPPET: extending -->
 *
 * <p/> <u>Example code:</u>
 *
 * <pre>
 * <!-- START SNIPPET: example -->
 * &lt;action name="someAction" class="com.examples.SomeAction"&gt;
 *     &lt;interceptor-ref name="static-params"&gt;
 *          &lt;param name="parse"&gt;true&lt;/param&gt;
 *     &lt;/interceptor-ref&gt;
 *     &lt;result name="success"&gt;good_result.ftl&lt;/result&gt;
 * &lt;/action&gt;
 * <!-- END SNIPPET: example -->
 * </pre>
 *
 * @author Patrick Lightbody
 */
public class StaticParametersInterceptor extends AbstractInterceptor {

    private boolean parse;
    
    private static final Log LOG = LogFactory.getLog(StaticParametersInterceptor.class);

    public void setParse(String value) {
        this.parse = Boolean.valueOf(value).booleanValue();
    }

    public String intercept(ActionInvocation invocation) throws Exception {
        ActionConfig config = invocation.getProxy().getConfig();
        Object action = invocation.getAction();

        final Map parameters = config.getParams();

        if (LOG.isDebugEnabled()) {
            LOG.debug("Setting static parameters " + parameters);
        }

        // for actions marked as Parameterizable, pass the static parameters directly
        if (action instanceof Parameterizable) {
            ((Parameterizable) action).setParams(parameters);
        }

        if (parameters != null) {
            final ValueStack stack = ActionContext.getContext().getValueStack();

            for (Iterator iterator = parameters.entrySet().iterator();
                 iterator.hasNext();) {
                Map.Entry entry = (Map.Entry) iterator.next();
                stack.setValue(entry.getKey().toString(), entry.getValue());
                Object val = entry.getValue();
                if (parse && val instanceof String) {
                    val = TextParseUtil.translateVariables((String) val, stack);
                }
                stack.setValue(entry.getKey().toString(), val);
            }
        }
        return invocation.invoke();
    }
}