/*
* 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.ValidationAware;
import com.opensymphony.xwork2.inject.Inject;
import com.opensymphony.xwork2.config.entities.ActionConfig;
import com.opensymphony.xwork2.util.ValueStack;
import com.opensymphony.xwork2.util.ClearableValueStack;
import com.opensymphony.xwork2.util.ValueStackFactory;
import com.opensymphony.xwork2.util.LocalizedTextUtil;
import com.opensymphony.xwork2.util.reflection.ReflectionContextState;
import com.opensymphony.xwork2.util.logging.Logger;
import com.opensymphony.xwork2.util.logging.LoggerFactory;
import java.util.Map;
/**
* <!-- START SNIPPET: description -->
*
* The aim of this Interceptor is to alias a named parameter to a different named parameter. By acting as the glue
* between actions sharing similiar parameters (but with different names), it can help greatly with action chaining.
*
* <p/> Action's alias expressions should be in the form of <code>#{ "name1" : "alias1", "name2" : "alias2" }</code>.
* This means that assuming an action (or something else in the stack) has a value for the expression named <i>name1</i> and the
* action this interceptor is applied to has a setter named <i>alias1</i>, <i>alias1</i> will be set with the value from
* <i>name1</i>.
*
* <!-- END SNIPPET: description -->
*
* <p/> <u>Interceptor parameters:</u>
*
* <!-- START SNIPPET: parameters -->
*
* <ul>
*
* <li>aliasesKey (optional) - the name of the action parameter to look for the alias map (by default this is
* <i>aliases</i>).</li>
*
* </ul>
*
* <!-- END SNIPPET: parameters -->
*
* <p/> <u>Extending the interceptor:</u>
*
* <p/>
*
* <!-- START SNIPPET: extending -->
*
* This interceptor does not have any known extension points.
*
* <!-- END SNIPPET: extending -->
*
* <p/> <u>Example code:</u>
*
* <pre>
* <!-- START SNIPPET: example -->
* <action name="someAction" class="com.examples.SomeAction">
* <!-- The value for the foo parameter will be applied as if it were named bar -->
* <param name="aliases">#{ 'foo' : 'bar' }</param>
*
* <interceptor-ref name="alias"/>
* <interceptor-ref name="basicStack"/>
* <result name="success">good_result.ftl</result>
* </action>
* <!-- END SNIPPET: example -->
* </pre>
*
* @author Matthew Payne
*/
public class AliasInterceptor extends AbstractInterceptor {
private static final Logger LOG = LoggerFactory.getLogger(AliasInterceptor.class);
private static final String DEFAULT_ALIAS_KEY = "aliases";
protected String aliasesKey = DEFAULT_ALIAS_KEY;
protected ValueStackFactory valueStackFactory;
static boolean devMode = false;
@Inject("devMode")
public static void setDevMode(String mode) {
devMode = "true".equals(mode);
}
@Inject
public void setValueStackFactory(ValueStackFactory valueStackFactory) {
this.valueStackFactory = valueStackFactory;
}
/**
* Sets the name of the action parameter to look for the alias map.
* <p/>
* Default is <code>aliases</code>.
*
* @param aliasesKey the name of the action parameter
*/
public void setAliasesKey(String aliasesKey) {
this.aliasesKey = aliasesKey;
}
@Override public String intercept(ActionInvocation invocation) throws Exception {
ActionConfig config = invocation.getProxy().getConfig();
ActionContext ac = invocation.getInvocationContext();
Object action = invocation.getAction();
// get the action's parameters
final Map<String, String> parameters = config.getParams();
if (parameters.containsKey(aliasesKey)) {
String aliasExpression = parameters.get(aliasesKey);
ValueStack stack = ac.getValueStack();
Object obj = stack.findValue(aliasExpression);
if (obj != null && obj instanceof Map) {
//get secure stack
ValueStack newStack = valueStackFactory.createValueStack(stack);
boolean clearableStack = newStack instanceof ClearableValueStack;
if (clearableStack) {
//if the stack's context can be cleared, do that to prevent OGNL
//from having access to objects in the stack, see XW-641
((ClearableValueStack)newStack).clearContextValues();
Map<String, Object> context = newStack.getContext();
ReflectionContextState.setCreatingNullObjects(context, true);
ReflectionContextState.setDenyMethodExecution(context, true);
ReflectionContextState.setReportingConversionErrors(context, true);
//keep locale from original context
context.put(ActionContext.LOCALE, stack.getContext().get(ActionContext.LOCALE));
}
// override
Map aliases = (Map) obj;
for (Object o : aliases.entrySet()) {
Map.Entry entry = (Map.Entry) o;
String name = entry.getKey().toString();
String alias = (String) entry.getValue();
Object value = stack.findValue(name);
if (null == value) {
// workaround
Map<String, Object> contextParameters = ActionContext.getContext().getParameters();
if (null != contextParameters) {
value = contextParameters.get(name);
}
}
if (null != value) {
try {
newStack.setValue(alias, value);
} catch (RuntimeException e) {
if (devMode) {
String developerNotification = LocalizedTextUtil.findText(ParametersInterceptor.class, "devmode.notification", ActionContext.getContext().getLocale(), "Developer Notification:\n{0}", new Object[]{
"Unexpected Exception caught setting '" + entry.getKey() + "' on '" + action.getClass() + ": " + e.getMessage()
});
LOG.error(developerNotification);
if (action instanceof ValidationAware) {
((ValidationAware) action).addActionMessage(developerNotification);
}
}
}
}
}
if (clearableStack && (stack.getContext() != null) && (newStack.getContext() != null))
stack.getContext().put(ActionContext.CONVERSION_ERRORS, newStack.getContext().get(ActionContext.CONVERSION_ERRORS));
} else {
LOG.debug("invalid alias expression:" + aliasesKey);
}
}
return invocation.invoke();
}
}
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