Environment.java

package org.batfish.datamodel.assertion;

import java.util.concurrent.ConcurrentMap;

import org.batfish.common.BatfishException;
import org.batfish.common.plugin.IBatfish;

import com.fasterxml.jackson.databind.node.ArrayNode;
import com.fasterxml.jackson.databind.node.JsonNodeFactory;
import com.jayway.jsonpath.Configuration;
import com.jayway.jsonpath.JsonPath;
import com.jayway.jsonpath.PathNotFoundException;

public class Environment {

   private IBatfish _batfish;

   private Configuration _configuration;

   private final Object _jsonObject;

   private ConcurrentMap<String, ArrayNode> _pathCache;

   public Environment(IBatfish batfish, Object jsonObject,
         ConcurrentMap<String, ArrayNode> pathCache, Configuration c) {
      _batfish = batfish;
      _pathCache = pathCache;
      _jsonObject = jsonObject;
      _configuration = c;
   }

   public ArrayNode computePath(String path) {
      ArrayNode pathResult = _pathCache.get(path);
      if (pathResult == null) {
         JsonPath jsonPath = JsonPath.compile(path);

         try {
            pathResult = jsonPath.read(_jsonObject, _configuration);
         }
         catch (PathNotFoundException e) {
            pathResult = JsonNodeFactory.instance.arrayNode();
         }
         catch (Exception e) {
            throw new BatfishException("Error reading JSON path: " + path, e);
         }
         _pathCache.put(path, pathResult);
      }
      return pathResult;
   }

   public IBatfish getBatfish() {
      return _batfish;
   }

   public Object getJsonObject() {
      return _jsonObject;
   }

}