Cache values of JsonObject#findProperty using CachedValuesManager

Cache is invalidated on every change in containing PSI file.

json/gen/com/intellij/json/JsonParser.java

@@ -1,18 +1,18 @@
 // This is a generated file. Not intended for manual editing.
 package com.intellij.json;
 
-import com.intellij.lang.ASTNode;
 import com.intellij.lang.PsiBuilder;
 import com.intellij.lang.PsiBuilder.Marker;
-import com.intellij.lang.PsiParser;
-import com.intellij.psi.tree.IElementType;
-import com.intellij.psi.tree.TokenSet;
-
 import static com.intellij.json.JsonElementTypes.*;
 import static com.intellij.json.psi.JsonParserUtil.*;
+import com.intellij.psi.tree.IElementType;
+import com.intellij.lang.ASTNode;
+import com.intellij.psi.tree.TokenSet;
+import com.intellij.lang.PsiParser;
+import com.intellij.lang.LightPsiParser;
 
 @SuppressWarnings({"SimplifiableIfStatement", "UnusedAssignment"})
-public class JsonParser implements PsiParser {
+public class JsonParser implements PsiParser, LightPsiParser {
 
   public ASTNode parse(IElementType t, PsiBuilder b) {
     parseLight(t, b);

json/gen/com/intellij/json/psi/impl/JsonObjectImpl.java

@@ -11,7 +11,7 @@ import static com.intellij.json.JsonElementTypes.*;
 import com.intellij.json.psi.*;
 import com.intellij.navigation.ItemPresentation;
 
-public class JsonObjectImpl extends JsonContainerImpl implements JsonObject {
+public class JsonObjectImpl extends JsonObjectMixin implements JsonObject {
 
   public JsonObjectImpl(ASTNode node) {
     super(node);
@@ -28,11 +28,6 @@ public class JsonObjectImpl extends JsonContainerImpl implements JsonObject {
     return PsiTreeUtil.getChildrenOfTypeAsList(this, JsonProperty.class);
   }
 
-  @Nullable
-  public JsonProperty findProperty(String name) {
-    return JsonPsiImplUtils.findProperty(this, name);
-  }
-
   @Nullable
   public ItemPresentation getPresentation() {
     return JsonPsiImplUtils.getPresentation(this);

json/src/com/intellij/json/psi/impl/JsonObjectMixin.java

@@ -0,0 +1,60 @@
+/*
+ * Copyright 2000-2015 JetBrains s.r.o.
+ *
+ * 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.intellij.json.psi.impl;
+
+import com.intellij.json.psi.JsonObject;
+import com.intellij.json.psi.JsonProperty;
+import com.intellij.lang.ASTNode;
+import com.intellij.psi.util.CachedValueProvider;
+import com.intellij.psi.util.CachedValuesManager;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import java.util.HashMap;
+import java.util.Map;
+
+/**
+ * @author Mikhail Golubev
+ */
+public abstract class JsonObjectMixin extends JsonContainerImpl implements JsonObject {
+  private final CachedValueProvider<Map<String, JsonProperty>> myPropertyCache =
+    new CachedValueProvider<Map<String, JsonProperty>>() {
+      @Nullable
+      @Override
+      public Result<Map<String, JsonProperty>> compute() {
+        final Map<String, JsonProperty> cache = new HashMap<String, JsonProperty>();
+        for (JsonProperty property : getPropertyList()) {
+          final String propertyName = property.getName();
+          // Preserve the old behavior - return the first value in findProperty()
+          if (!cache.containsKey(propertyName)) {
+            cache.put(propertyName, property);
+          }
+        }
+        // Cached value is invalidated every time file containing this object is modified
+        return CachedValueProvider.Result.createSingleDependency(cache, JsonObjectMixin.this);
+      }
+    };
+
+  public JsonObjectMixin(@NotNull ASTNode node) {
+    super(node);
+  }
+
+  @Nullable
+  @Override
+  public JsonProperty findProperty(@NotNull String name) {
+    return CachedValuesManager.getCachedValue(this, myPropertyCache).get(name);
+  }
+}

json/src/com/intellij/json/psi/impl/JsonPsiImplUtils.java

@@ -197,17 +197,6 @@ public class JsonPsiImplUtils {
     JsonPsiChangeUtils.removeCommaSeparatedFromList(myNode, myNode.getTreeParent());
   }
 
-  @Nullable
-  public static JsonProperty findProperty(@NotNull JsonObject object, @NotNull String name) {
-    final Collection<JsonProperty> properties = PsiTreeUtil.findChildrenOfType(object, JsonProperty.class);
-    for (JsonProperty property : properties) {
-      if (property.getName().equals(name)) {
-        return property;
-      }
-    }
-    return null;
-  }
-
   @NotNull
   public static String getValue(@NotNull JsonStringLiteral literal) {
     return StringUtil.unescapeStringCharacters(JsonPsiUtil.stripQuotes(literal.getText()));

json/src/json.bnf

@@ -62,6 +62,7 @@ object ::= '{' object_element* '}' {
     findProperty
     getPresentation
   ]
+  mixin="com.intellij.json.psi.impl.JsonObjectMixin"
 }
 
 // Hackity-hack to parse array elements and properties even if separating commas are missing,