How to clear EhCache OnDemand

I found the following solution on Spring framework forum.

You can add following controller to your admin app, make sure the below URL is only available to you and not exposed to public.

In below code we are injecting CacheManager object, the I name used (ehCacheManager) might be different for your code.

After deploying below code visit http://localhost:8080/list-ehcache-objects and click on the cache names to clear them.


package com.mycompany.controller;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;

import javax.annotation.Resource;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import net.sf.ehcache.CacheManager;


import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.servlet.ModelAndView;
import org.springframework.web.servlet.mvc.ParameterizableViewController;

@Controller
public class EHCacheController  {
	
	@Resource(name="ehCacheManager")
	private CacheManager cacheManager;

    /* (non-Javadoc)
     * @see org.springframework.web.servlet.mvc.ParameterizableViewController#handleRequestInternal(javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse)
     */
    @SuppressWarnings("unchecked")
    @RequestMapping( value = "/list-ehcache-objects")
	protected String clear(Model viewModel, HttpServletRequest request, HttpServletResponse response) throws Exception {
	        HashMap model = new HashMap();
	        //Get all the active caches
	        List caches = new ArrayList(cacheManager.getCacheNames().length);
	        ArrayList cacheNamesList = new ArrayList();
	        String[] cacheNames = cacheManager.getCacheNames();
	        Iterator iter = Arrays.asList(cacheNames).iterator();
	        String cacheName = request.getParameter("cacheName");
	        while (iter.hasNext()){
	        	
	            // If the cache name has been passed from the request then flush it //
	            String cacheNameTest = (String) iter.next();
	            if (cacheNameTest.equalsIgnoreCase(cacheName)){
	                cacheManager.getCache(cacheNameTest).removeAll();
	            }
	            caches.add(cacheManager.getCache(cacheNameTest));
	            cacheNamesList.add(cacheNameTest);
	        }
	        //Stick the caches in the page model
	        model.put("caches", caches);
	        model.put("cacheNames", cacheNamesList);
	        viewModel.addAllAttributes(model);
	        return "layout/clearehcache";
	    }

    
	/**
	 * Setter for the EHCacheManager
	 * @param cacheManager
	 */
	public void setCacheManager(CacheManager cacheManager) {
		this.cacheManager = cacheManager;
	}
	
}

For my controller view I used the following, since I am using Thymeleaf the syntax will be different to that of JSP files.

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