com.github.nblair.web.ProfileConditionalDelegatingFilterProxy.java Source code

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Here is the source code for com.github.nblair.web.ProfileConditionalDelegatingFilterProxy.java

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/**
 * Board of Regents of the University of Wisconsin System
 * 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.github.nblair.web;

import java.io.IOException;

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;

import org.springframework.context.annotation.Profile;
import org.springframework.core.env.Environment;
import org.springframework.web.context.WebApplicationContext;
import org.springframework.web.filter.DelegatingFilterProxy;

/**
 * Subclass of {@link DelegatingFilterProxy} that allows for conditional execution of the 
 * delegate {@link Filter} if and only if the required spring {@link Profile}s are active.
 * 
 * If any or all of the required profiles are not active, the delegate {@link Filter#doFilter(ServletRequest, ServletResponse, FilterChain)} 
 * is not invoked ({@link FilterChain#doFilter(ServletRequest, ServletResponse)} is allowed to proceed).
 * 
 * @see Environment#acceptsProfiles(String...)
 * @author Nicholas Blair
 */
public class ProfileConditionalDelegatingFilterProxy extends DelegatingFilterProxy {

    private String[] requiredProfiles = new String[0];

    /**
     * 
     */
    public ProfileConditionalDelegatingFilterProxy() {
        super();
    }

    /**
     * @param delegate
     */
    public ProfileConditionalDelegatingFilterProxy(Filter delegate) {
        super(delegate);
    }

    /**
     * @param targetBeanName
     * @param wac
     */
    public ProfileConditionalDelegatingFilterProxy(String targetBeanName, WebApplicationContext wac) {
        super(targetBeanName, wac);
    }

    /**
     * @param targetBeanName
     */
    public ProfileConditionalDelegatingFilterProxy(String targetBeanName) {
        super(targetBeanName);
    }

    /**
     * 
     * @param requiredProfile
     * @return
     */
    public ProfileConditionalDelegatingFilterProxy setRequiredProfile(String requiredProfile) {
        this.requiredProfiles = new String[] { requiredProfile };
        return this;
    }

    /**
     * 
     * @param requiredProfiles
     * @return
     */
    public ProfileConditionalDelegatingFilterProxy setRequiredProfiles(String... requiredProfiles) {
        this.requiredProfiles = requiredProfiles;
        return this;
    }

    /**
     * @return the requiredProfiles
     */
    public String[] getRequiredProfiles() {
        return requiredProfiles;
    }

    /* (non-Javadoc)
     * @see org.springframework.web.filter.DelegatingFilterProxy#doFilter(javax.servlet.ServletRequest, javax.servlet.ServletResponse, javax.servlet.FilterChain)
     */
    @Override
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain filterChain)
            throws ServletException, IOException {
        if (requiredProfilesAreActive()) {
            super.doFilter(request, response, filterChain);
        } else {
            filterChain.doFilter(request, response);
        }
    }

    /**
     * Returns true if all the required profiles are active in the environment.
     * 
     * Note, even though {@link Environment#acceptsProfiles(String...)} is multi-valued, we have
     * to check each profile individually because ENvironment's method will return true if any of the arguments
     * are valid (not necessarily all).
     * 
     * @see Environment#acceptsProfiles(String...)
     * @return true if all {@link #getRequiredProfiles()} are active
     */
    protected boolean requiredProfilesAreActive() {
        if (requiredProfiles.length == 0) {
            return true;
        }
        Environment environment = findWebApplicationContext().getEnvironment();
        for (String profile : requiredProfiles) {
            if (!environment.acceptsProfiles(profile)) {
                return false;
            }
        }
        return true;
    }
}