Struts example source code file (AnnotationParameterFilterIntereptor.java)

This example Struts source code file (AnnotationParameterFilterIntereptor.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

abstractinterceptor, annotationparameterfilterintereptor, arraylist, exception, field, field, hashset, hashset, map, object, object, override, reflection, string, string, util

The Struts AnnotationParameterFilterIntereptor.java source code

package com.opensymphony.xwork2.interceptor.annotations;


import com.opensymphony.xwork2.Action;
import com.opensymphony.xwork2.ActionInvocation;
import com.opensymphony.xwork2.interceptor.AbstractInterceptor;
import com.opensymphony.xwork2.interceptor.Interceptor;
import com.opensymphony.xwork2.interceptor.ParameterFilterInterceptor;
import com.opensymphony.xwork2.interceptor.ParametersInterceptor;
import com.opensymphony.xwork2.util.AnnotationUtils;

import java.lang.reflect.Field;
import java.util.ArrayList;
import java.util.HashSet;
import java.util.List;
import java.util.Map;

/**
 * Annotation based version of {@link ParameterFilterInterceptor}.
 * <p/>
 * This {@link Interceptor} must be placed in the stack before the {@link ParametersInterceptor}
 * When a parameter matches a field that is marked {@link Blocked} then it is removed from
 * the parameter map.
 * <p/>
 * If an {@link Action} class is marked with {@link BlockByDefault} then all parameters are
 * removed unless a field on the Action exists and is marked with {@link Allowed}
 *
 * @author martin.gilday
 */
public class AnnotationParameterFilterIntereptor extends AbstractInterceptor {

    /* (non-Javadoc)
      * @see com.opensymphony.xwork2.interceptor.AbstractInterceptor#intercept(com.opensymphony.xwork2.ActionInvocation)
      */
    @Override public String intercept(ActionInvocation invocation) throws Exception {

        final Object action = invocation.getAction();
        Map<String, Object> parameters = invocation.getInvocationContext().getParameters();

        Object model = invocation.getStack().peek();
        if (model == action) {
            model = null;
        }

        boolean blockByDefault = action.getClass().isAnnotationPresent(BlockByDefault.class);
        List<Field> annotatedFields = new ArrayList();
        HashSet<String> paramsToRemove = new HashSet();

        if (blockByDefault) {
            AnnotationUtils.addAllFields(Allowed.class, action.getClass(), annotatedFields);
            if (model != null) {
                AnnotationUtils.addAllFields(Allowed.class, model.getClass(), annotatedFields);
            }

            for (String paramName : parameters.keySet()) {
                boolean allowed = false;

                for (Field field : annotatedFields) {
                    //TODO only matches exact field names.  need to change to it matches start of ognl expression
                    //i.e take param name up to first . (period) and match against that
                    if (field.getName().equals(paramName)) {
                        allowed = true;
                    }
                }

                if (!allowed) {
                    paramsToRemove.add(paramName);
                }
            }
        } else {
            AnnotationUtils.addAllFields(Blocked.class, action.getClass(), annotatedFields);
            if (model != null) {
                AnnotationUtils.addAllFields(Blocked.class, model.getClass(), annotatedFields);
            }

            for (String paramName : parameters.keySet()) {

                for (Field field : annotatedFields) {
                    //TODO only matches exact field names.  need to change to it matches start of ognl expression
                    //i.e take param name up to first . (period) and match against that
                    if (field.getName().equals(paramName)) {
                        paramsToRemove.add(paramName);
                    }
                }
            }
        }

        for (String aParamsToRemove : paramsToRemove) {
            parameters.remove(aParamsToRemove);
        }

        return invocation.invoke();
    }

}