com.opensymphony.xwork2.interceptor.AliasInterceptor Maven / Gradle / Ivy
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* 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 com.opensymphony.xwork2.interceptor;
import com.opensymphony.xwork2.ActionContext;
import com.opensymphony.xwork2.ActionInvocation;
import com.opensymphony.xwork2.XWorkConstants;
import com.opensymphony.xwork2.config.entities.ActionConfig;
import com.opensymphony.xwork2.inject.Inject;
import com.opensymphony.xwork2.util.ClearableValueStack;
import com.opensymphony.xwork2.util.Evaluated;
import com.opensymphony.xwork2.LocalizedTextProvider;
import com.opensymphony.xwork2.util.ValueStack;
import com.opensymphony.xwork2.util.ValueStackFactory;
import com.opensymphony.xwork2.util.reflection.ReflectionContextState;
import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;
import org.apache.struts2.dispatcher.HttpParameters;
import java.util.Map;
/**
*
*
* The aim of this Interceptor is to alias a named parameter to a different named parameter. By acting as the glue
* between actions sharing similar parameters (but with different names), it can help greatly with action chaining.
*
* Action's alias expressions should be in the form of #{ "name1" : "alias1", "name2" : "alias2" }.
* This means that assuming an action (or something else in the stack) has a value for the expression named name1 and the
* action this interceptor is applied to has a setter named alias1, alias1 will be set with the value from
* name1.
*
*
*
*
* Interceptor parameters:
*
*
*
*
*
* - aliasesKey (optional) - the name of the action parameter to look for the alias map (by default this is
* aliases).
*
*
*
*
*
* Extending the interceptor:
*
*
*
* This interceptor does not have any known extension points.
*
*
*
* Example code:
*
*
*
* <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>
*
*
*
* @author Matthew Payne
*/
public class AliasInterceptor extends AbstractInterceptor {
private static final Logger LOG = LogManager.getLogger(AliasInterceptor.class);
private static final String DEFAULT_ALIAS_KEY = "aliases";
protected String aliasesKey = DEFAULT_ALIAS_KEY;
protected ValueStackFactory valueStackFactory;
protected LocalizedTextProvider localizedTextProvider;
protected boolean devMode = false;
@Inject(XWorkConstants.DEV_MODE)
public void setDevMode(String mode) {
this.devMode = Boolean.parseBoolean(mode);
}
@Inject
public void setValueStackFactory(ValueStackFactory valueStackFactory) {
this.valueStackFactory = valueStackFactory;
}
@Inject
public void setLocalizedTextProvider(LocalizedTextProvider localizedTextProvider) {
this.localizedTextProvider = localizedTextProvider;
}
/**
*
* Sets the name of the action parameter to look for the alias map.
*
*
*
* Default is aliases.
*
*
* @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 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 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();
Evaluated value = new Evaluated(stack.findValue(name));
if (!value.isDefined()) {
// workaround
HttpParameters contextParameters = ActionContext.getContext().getParameters();
if (null != contextParameters) {
value = new Evaluated(contextParameters.get(name));
}
}
if (value.isDefined()) {
try {
newStack.setValue(alias, value.get());
} catch (RuntimeException e) {
if (devMode) {
String developerNotification = localizedTextProvider.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();
}
}