From bf33697891aaadc4fae947101e433d4afb3ca41b Mon Sep 17 00:00:00 2001
From: gauravgupta <ggupta22@gmail.com>
Date: Sun, 11 Oct 2015 18:09:47 -0400
Subject: [PATCH 1/4] Externalized the cache using CacheProvider spi.

Set the CacheProvider in the Configuration:
Configuration
            .builder()
            .mappingProvider(new <<Implementation of mapping provider>>)
            .jsonProvider(new <<Implementation of JsonProvider>>)
            .cacheProvider(new <<implementation of CacheProvider>>)
            .build();
---
 .../com/jayway/jsonpath/Configuration.java    |  41 ++++++-
 .../jsonpath/internal/DefaultsImpl.java       |  11 +-
 .../jayway/jsonpath/internal/JsonReader.java  |   8 +-
 .../jsonpath/internal/PathCompiler.java       |  12 +-
 .../jsonpath/spi/cache/CacheProvider.java     |  23 ++++
 .../jsonpath/spi/cache/DefaultCache.java      | 116 ++++++++++++++++++
 6 files changed, 201 insertions(+), 10 deletions(-)
 create mode 100644 json-path/src/main/java/com/jayway/jsonpath/spi/cache/CacheProvider.java
 create mode 100644 json-path/src/main/java/com/jayway/jsonpath/spi/cache/DefaultCache.java

diff --git a/json-path/src/main/java/com/jayway/jsonpath/Configuration.java b/json-path/src/main/java/com/jayway/jsonpath/Configuration.java
index 1a591ea8..cebb3a99 100644
--- a/json-path/src/main/java/com/jayway/jsonpath/Configuration.java
+++ b/json-path/src/main/java/com/jayway/jsonpath/Configuration.java
@@ -15,6 +15,8 @@
 package com.jayway.jsonpath;
 
 import com.jayway.jsonpath.internal.DefaultsImpl;
+import com.jayway.jsonpath.spi.cache.CacheProvider;
+import com.jayway.jsonpath.spi.cache.DefaultCache;
 import com.jayway.jsonpath.spi.json.JsonProvider;
 import com.jayway.jsonpath.spi.mapper.MappingProvider;
 
@@ -55,14 +57,16 @@ public class Configuration {
     private final MappingProvider mappingProvider;
     private final Set<Option> options;
     private final Collection<EvaluationListener> evaluationListeners;
+    private final CacheProvider cacheProvider;
 
-    private Configuration(JsonProvider jsonProvider, MappingProvider mappingProvider, EnumSet<Option> options, Collection<EvaluationListener> evaluationListeners) {
+    private Configuration(JsonProvider jsonProvider, MappingProvider mappingProvider, CacheProvider cacheProvider, EnumSet<Option> options, Collection<EvaluationListener> evaluationListeners) {
         notNull(jsonProvider, "jsonProvider can not be null");
         notNull(mappingProvider, "mappingProvider can not be null");
         notNull(options, "setOptions can not be null");
         notNull(evaluationListeners, "evaluationListeners can not be null");
         this.jsonProvider = jsonProvider;
         this.mappingProvider = mappingProvider;
+        this.cacheProvider = cacheProvider;
         this.options = Collections.unmodifiableSet(options);
         this.evaluationListeners = Collections.unmodifiableCollection(evaluationListeners);
     }
@@ -126,6 +130,23 @@ public class Configuration {
     public MappingProvider mappingProvider() {
         return mappingProvider;
     }
+    
+    /**
+     * Creates a new Configuration based on the given {@link com.jayway.jsonpath.spi.cache.CacheProvider}
+     * @param newCacheProvider cache provider to use in new configuration
+     * @return a new configuration
+     */
+    public Configuration CacheProvider(CacheProvider newCacheProvider) {
+        return Configuration.builder().jsonProvider(jsonProvider).mappingProvider(mappingProvider).cacheProvider(newCacheProvider).options(options).evaluationListener(evaluationListeners).build();
+    }
+
+    /**
+     * Returns {@link com.jayway.jsonpath.spi.cache.CacheProvider} used by this configuration
+     * @return cacheProvider used
+     */
+    public CacheProvider CacheProvider() {
+        return cacheProvider;
+    }
 
     /**
      * Creates a new configuration by adding the new options to the options used in this configuration.
@@ -189,6 +210,7 @@ public class Configuration {
 
         private JsonProvider jsonProvider;
         private MappingProvider mappingProvider;
+        private CacheProvider cacheProvider = new DefaultCache(200);
         private EnumSet<Option> options = EnumSet.noneOf(Option.class);
         private Collection<EvaluationListener> evaluationListener = new ArrayList<EvaluationListener>();
 
@@ -201,6 +223,11 @@ public class Configuration {
             this.mappingProvider = provider;
             return this;
         }
+        
+        public ConfigurationBuilder cacheProvider(CacheProvider provider) {
+            this.cacheProvider = provider;
+            return this;
+        }
 
         public ConfigurationBuilder options(Option... flags) {
             if(flags.length > 0) {
@@ -233,8 +260,11 @@ public class Configuration {
                 if (mappingProvider == null){
                     mappingProvider = defaults.mappingProvider();
                 }
+                if (cacheProvider == null){
+                    cacheProvider = defaults.cacheProvider();
+                }
             }
-            return new Configuration(jsonProvider, mappingProvider, options, evaluationListener);
+            return new Configuration(jsonProvider, mappingProvider, cacheProvider, options, evaluationListener);
         }
     }
 
@@ -257,6 +287,13 @@ public class Configuration {
          * @return default mapping provider
          */
         MappingProvider mappingProvider();
+        
+        /**
+         * Returns the default {@link com.jayway.jsonpath.spi.cache.CacheProvider}
+         *
+         * @return default cache provider
+         */
+        CacheProvider cacheProvider();
 
     }
 }
diff --git a/json-path/src/main/java/com/jayway/jsonpath/internal/DefaultsImpl.java b/json-path/src/main/java/com/jayway/jsonpath/internal/DefaultsImpl.java
index d56128b1..5023edd9 100644
--- a/json-path/src/main/java/com/jayway/jsonpath/internal/DefaultsImpl.java
+++ b/json-path/src/main/java/com/jayway/jsonpath/internal/DefaultsImpl.java
@@ -5,6 +5,8 @@ import java.util.Set;
 
 import com.jayway.jsonpath.Configuration.Defaults;
 import com.jayway.jsonpath.Option;
+import com.jayway.jsonpath.spi.cache.DefaultCache;
+import com.jayway.jsonpath.spi.cache.CacheProvider;
 import com.jayway.jsonpath.spi.json.JsonProvider;
 import com.jayway.jsonpath.spi.json.JsonSmartJsonProvider;
 import com.jayway.jsonpath.spi.mapper.JsonSmartMappingProvider;
@@ -15,6 +17,8 @@ public final class DefaultsImpl implements Defaults {
   public static final DefaultsImpl INSTANCE = new DefaultsImpl();
 
   private final MappingProvider mappingProvider = new JsonSmartMappingProvider();
+  
+  private final CacheProvider cacheProvider = new DefaultCache(200);
 
   @Override
   public JsonProvider jsonProvider() {
@@ -32,6 +36,11 @@ public final class DefaultsImpl implements Defaults {
   }
 
   private DefaultsImpl() {
-  };
+  }
+
+	@Override
+	public CacheProvider cacheProvider() {
+		return cacheProvider;
+	};
 
 }
diff --git a/json-path/src/main/java/com/jayway/jsonpath/internal/JsonReader.java b/json-path/src/main/java/com/jayway/jsonpath/internal/JsonReader.java
index 7f207802..a190252c 100644
--- a/json-path/src/main/java/com/jayway/jsonpath/internal/JsonReader.java
+++ b/json-path/src/main/java/com/jayway/jsonpath/internal/JsonReader.java
@@ -132,7 +132,13 @@ public class JsonReader implements ParseContext, DocumentContext {
     @Override
     public <T> T read(String path, Predicate... filters) {
         notEmpty(path, "path can not be null or empty");
-        return read(compile(path, filters));
+        JsonPath cached = configuration.CacheProvider().get(path);
+        if(cached != null){
+        	return read(cached);
+        }else {
+        	return read(compile(path, filters));
+        }
+
     }
 
     @Override
diff --git a/json-path/src/main/java/com/jayway/jsonpath/internal/PathCompiler.java b/json-path/src/main/java/com/jayway/jsonpath/internal/PathCompiler.java
index f9056d78..8a3ae9bf 100644
--- a/json-path/src/main/java/com/jayway/jsonpath/internal/PathCompiler.java
+++ b/json-path/src/main/java/com/jayway/jsonpath/internal/PathCompiler.java
@@ -66,12 +66,12 @@ public class PathCompiler {
                 fail("Path must not end wid a scan operation '..'");
             }
             LinkedList filterStack = new LinkedList<Predicate>(asList(filters));
-            String cacheKey = Utils.concat(path, filterStack.toString());
-            Path p = cache.get(cacheKey);
-            if (p == null) {
-                p = new PathCompiler(path.trim(), filterStack).compile();
-                cache.put(cacheKey, p);
-            }
+//            String cacheKey = Utils.concat(path, filterStack.toString());
+//            Path p = cache.get(cacheKey);
+//            if (p == null) {
+            Path p = new PathCompiler(path.trim(), filterStack).compile();
+//                cache.put(cacheKey, p);
+//            }
             return p;
         } catch (Exception e) {
             InvalidPathException ipe;
diff --git a/json-path/src/main/java/com/jayway/jsonpath/spi/cache/CacheProvider.java b/json-path/src/main/java/com/jayway/jsonpath/spi/cache/CacheProvider.java
new file mode 100644
index 00000000..6299a4f1
--- /dev/null
+++ b/json-path/src/main/java/com/jayway/jsonpath/spi/cache/CacheProvider.java
@@ -0,0 +1,23 @@
+package com.jayway.jsonpath.spi.cache;
+
+import com.jayway.jsonpath.InvalidJsonException;
+import com.jayway.jsonpath.JsonPath;
+
+public interface CacheProvider {
+
+	/**
+     * Get the Cached JsonPath
+     * @param key cache key to lookup the JsonPath
+     * @return JsonPath
+     */
+	public JsonPath get(String key);
+	
+	/**
+     * Add JsonPath to the cache
+     * @param key cache key to store the JsonPath
+     * @param value JsonPath to be cached
+     * @return void
+     * @throws InvalidJsonException
+     */
+	public void put(String key, JsonPath value);
+}
diff --git a/json-path/src/main/java/com/jayway/jsonpath/spi/cache/DefaultCache.java b/json-path/src/main/java/com/jayway/jsonpath/spi/cache/DefaultCache.java
new file mode 100644
index 00000000..48eae99a
--- /dev/null
+++ b/json-path/src/main/java/com/jayway/jsonpath/spi/cache/DefaultCache.java
@@ -0,0 +1,116 @@
+/*
+ * Copyright 2011 the original author or authors.
+ * Licensed 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.jayway.jsonpath.spi.cache;
+
+import java.util.Deque;
+import java.util.LinkedList;
+import java.util.Map;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.locks.ReentrantLock;
+
+import com.jayway.jsonpath.JsonPath;
+
+/*
+ * LRU implementation copied from com.jayway.jsonpath.internal.Cache
+ * Will have the same bugs
+ */
+
+public class DefaultCache implements CacheProvider{
+
+    private final ReentrantLock lock = new ReentrantLock();
+
+    private final Map<String, JsonPath> map = new ConcurrentHashMap<String, JsonPath>();
+    private final Deque<String> queue = new LinkedList<String>();
+    private final int limit;
+
+    public DefaultCache(int limit) {
+        this.limit = limit;
+    }
+
+    public void put(String key, JsonPath value) {
+        JsonPath oldValue = map.put(key, value);
+        if (oldValue != null) {
+            removeThenAddKey(key);
+        } else {
+            addKey(key);
+        }
+        if (map.size() > limit) {
+            map.remove(removeLast());
+        }
+    }
+
+    public JsonPath get(String key) {
+        if(map.containsKey(key)){
+            removeThenAddKey(key);
+        }
+        return map.get(key);
+    }
+
+    private void addKey(String key) {
+        lock.lock();
+        try {
+            queue.addFirst(key);
+        } finally {
+            lock.unlock();
+        }
+    }
+
+    private String removeLast() {
+        lock.lock();
+        try {
+            final String removedKey = queue.removeLast();
+            return removedKey;
+        } finally {
+            lock.unlock();
+        }
+    }
+
+    private void removeThenAddKey(String key) {
+        lock.lock();
+        try {
+            queue.removeFirstOccurrence(key);
+            queue.addFirst(key);
+        } finally {
+            lock.unlock();
+        }
+
+    }
+
+    private void removeFirstOccurrence(String key) {
+        lock.lock();
+        try {
+            queue.removeFirstOccurrence(key);
+        } finally {
+            lock.unlock();
+        }
+    }
+
+    public JsonPath getSilent(String key) {
+        return map.get(key);
+    }
+
+    public void remove(String key) {
+        removeFirstOccurrence(key);
+        map.remove(key);
+    }
+
+    public int size() {
+        return map.size();
+    }
+
+    public String toString() {
+        return map.toString();
+    }
+}
\ No newline at end of file

From eebfd8bbda5137fa0cf899778575584aed234387 Mon Sep 17 00:00:00 2001
From: gauravgupta <ggupta22@gmail.com>
Date: Sun, 11 Oct 2015 18:20:52 -0400
Subject: [PATCH 2/4] Updating the cache on cache miss

---
 .../com/jayway/jsonpath/internal/JsonReader.java    | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/json-path/src/main/java/com/jayway/jsonpath/internal/JsonReader.java b/json-path/src/main/java/com/jayway/jsonpath/internal/JsonReader.java
index a190252c..c6893599 100644
--- a/json-path/src/main/java/com/jayway/jsonpath/internal/JsonReader.java
+++ b/json-path/src/main/java/com/jayway/jsonpath/internal/JsonReader.java
@@ -23,6 +23,8 @@ import com.jayway.jsonpath.ParseContext;
 import com.jayway.jsonpath.Predicate;
 import com.jayway.jsonpath.ReadContext;
 import com.jayway.jsonpath.TypeRef;
+import com.jayway.jsonpath.spi.cache.CacheProvider;
+
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -132,11 +134,14 @@ public class JsonReader implements ParseContext, DocumentContext {
     @Override
     public <T> T read(String path, Predicate... filters) {
         notEmpty(path, "path can not be null or empty");
-        JsonPath cached = configuration.CacheProvider().get(path);
-        if(cached != null){
-        	return read(cached);
+        CacheProvider cache = configuration.CacheProvider();
+        JsonPath jsonPath = cache.get(path);
+        if(jsonPath != null){
+        	return read(jsonPath);
         }else {
-        	return read(compile(path, filters));
+        	jsonPath = compile(path, filters);
+        	cache.put(path, jsonPath);
+        	return read(jsonPath);
         }
 
     }

From 9bc0f8b213b7ac9d14904f76d43ddcd90d3433e7 Mon Sep 17 00:00:00 2001
From: gauravgupta <ggupta22@gmail.com>
Date: Mon, 12 Oct 2015 17:44:44 -0400
Subject: [PATCH 3/4] Added filters to the cache key #94

---
 .../jayway/jsonpath/internal/JsonReader.java  |  9 +++++-
 .../jsonpath/internal/JsonReaderTest.java     | 30 +++++++++++++++++++
 2 files changed, 38 insertions(+), 1 deletion(-)
 create mode 100644 json-path/src/test/java/com/jayway/jsonpath/internal/JsonReaderTest.java

diff --git a/json-path/src/main/java/com/jayway/jsonpath/internal/JsonReader.java b/json-path/src/main/java/com/jayway/jsonpath/internal/JsonReader.java
index c6893599..9e7b9cc2 100644
--- a/json-path/src/main/java/com/jayway/jsonpath/internal/JsonReader.java
+++ b/json-path/src/main/java/com/jayway/jsonpath/internal/JsonReader.java
@@ -32,11 +32,13 @@ import java.io.File;
 import java.io.FileInputStream;
 import java.io.IOException;
 import java.io.InputStream;
+import java.util.LinkedList;
 import java.util.List;
 
 import static com.jayway.jsonpath.JsonPath.compile;
 import static com.jayway.jsonpath.internal.Utils.notEmpty;
 import static com.jayway.jsonpath.internal.Utils.notNull;
+import static java.util.Arrays.asList;
 
 public class JsonReader implements ParseContext, DocumentContext {
 
@@ -135,7 +137,12 @@ public class JsonReader implements ParseContext, DocumentContext {
     public <T> T read(String path, Predicate... filters) {
         notEmpty(path, "path can not be null or empty");
         CacheProvider cache = configuration.CacheProvider();
-        JsonPath jsonPath = cache.get(path);
+        
+        path = path.trim();
+        LinkedList filterStack = new LinkedList<Predicate>(asList(filters));
+        String cacheKey = Utils.concat(path, filterStack.toString());
+        
+        JsonPath jsonPath = cache.get(cacheKey);
         if(jsonPath != null){
         	return read(jsonPath);
         }else {
diff --git a/json-path/src/test/java/com/jayway/jsonpath/internal/JsonReaderTest.java b/json-path/src/test/java/com/jayway/jsonpath/internal/JsonReaderTest.java
new file mode 100644
index 00000000..efecffef
--- /dev/null
+++ b/json-path/src/test/java/com/jayway/jsonpath/internal/JsonReaderTest.java
@@ -0,0 +1,30 @@
+package com.jayway.jsonpath.internal;
+
+import static org.junit.Assert.*;
+
+import java.util.List;
+
+import org.assertj.core.api.Assertions;
+import org.junit.Test;
+
+import com.jayway.jsonpath.BaseTest;
+import com.jayway.jsonpath.Criteria;
+import com.jayway.jsonpath.Filter;
+import com.jayway.jsonpath.JsonPath;
+
+public class JsonReaderTest extends BaseTest {
+
+	@Test
+    public void cached_path_with_predicates() {
+
+        Filter feq = Filter.filter(Criteria.where("category").eq("reference"));
+        Filter fne = Filter.filter(Criteria.where("category").ne("reference"));
+
+        List<String> eq = JsonPath.parse(JSON_DOCUMENT).read("$.store.book[?].category", feq);
+        List<String> ne = JsonPath.parse(JSON_DOCUMENT).read("$.store.book[?].category", fne);
+
+        Assertions.assertThat(eq).contains("reference");
+        Assertions.assertThat(ne).doesNotContain("reference");
+    }
+
+}

From f25ec6c0cdf70fb8bbc46e1514d4ca55809e9a5c Mon Sep 17 00:00:00 2001
From: gauravgupta <ggupta22@gmail.com>
Date: Tue, 13 Oct 2015 19:22:33 -0400
Subject: [PATCH 4/4] fixed the cache key and the unit test (use the same key
 when fetching and looking up cache) #94

---
 .../main/java/com/jayway/jsonpath/internal/JsonReader.java | 2 +-
 .../java/com/jayway/jsonpath/internal/JsonReaderTest.java  | 7 +++++--
 2 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/json-path/src/main/java/com/jayway/jsonpath/internal/JsonReader.java b/json-path/src/main/java/com/jayway/jsonpath/internal/JsonReader.java
index 9e7b9cc2..c896ed9b 100644
--- a/json-path/src/main/java/com/jayway/jsonpath/internal/JsonReader.java
+++ b/json-path/src/main/java/com/jayway/jsonpath/internal/JsonReader.java
@@ -147,7 +147,7 @@ public class JsonReader implements ParseContext, DocumentContext {
         	return read(jsonPath);
         }else {
         	jsonPath = compile(path, filters);
-        	cache.put(path, jsonPath);
+        	cache.put(cacheKey, jsonPath);
         	return read(jsonPath);
         }
 
diff --git a/json-path/src/test/java/com/jayway/jsonpath/internal/JsonReaderTest.java b/json-path/src/test/java/com/jayway/jsonpath/internal/JsonReaderTest.java
index efecffef..7cac7629 100644
--- a/json-path/src/test/java/com/jayway/jsonpath/internal/JsonReaderTest.java
+++ b/json-path/src/test/java/com/jayway/jsonpath/internal/JsonReaderTest.java
@@ -9,6 +9,7 @@ import org.junit.Test;
 
 import com.jayway.jsonpath.BaseTest;
 import com.jayway.jsonpath.Criteria;
+import com.jayway.jsonpath.DocumentContext;
 import com.jayway.jsonpath.Filter;
 import com.jayway.jsonpath.JsonPath;
 
@@ -19,9 +20,11 @@ public class JsonReaderTest extends BaseTest {
 
         Filter feq = Filter.filter(Criteria.where("category").eq("reference"));
         Filter fne = Filter.filter(Criteria.where("category").ne("reference"));
+        
+        DocumentContext JsonDoc = JsonPath.parse(JSON_DOCUMENT);
 
-        List<String> eq = JsonPath.parse(JSON_DOCUMENT).read("$.store.book[?].category", feq);
-        List<String> ne = JsonPath.parse(JSON_DOCUMENT).read("$.store.book[?].category", fne);
+        List<String> eq = JsonDoc.read("$.store.book[?].category", feq);
+        List<String> ne = JsonDoc.read("$.store.book[?].category", fne);
 
         Assertions.assertThat(eq).contains("reference");
         Assertions.assertThat(ne).doesNotContain("reference");