don't highlight named groups in Java 1.7 regular expressions as errors (IDEA-80456)

java/java-impl/java-impl.iml

@@ -31,6 +31,7 @@
     <orderEntry type="library" name="Guava" level="project" />
     <orderEntry type="library" scope="TEST" name="JUnit4" level="project" />
     <orderEntry type="module" module-name="java-psi-impl" exported="" />
+    <orderEntry type="module" module-name="RegExpSupport" />
   </component>
   <component name="copyright">
     <Base>

java/java-impl/src/com/intellij/psi/impl/JavaRegExpHost.java

@@ -0,0 +1,65 @@
+/*
+ * Copyright 2000-2012 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.psi.impl;
+
+import com.intellij.openapi.module.Module;
+import com.intellij.openapi.module.ModuleUtil;
+import com.intellij.openapi.projectRoots.JavaSdk;
+import com.intellij.openapi.projectRoots.JavaSdkVersion;
+import com.intellij.openapi.projectRoots.Sdk;
+import com.intellij.openapi.roots.ModuleRootManager;
+import org.intellij.lang.regexp.RegExpLanguageHost;
+import org.intellij.lang.regexp.psi.RegExpGroup;
+
+/**
+ * @author yole
+ */
+public class JavaRegExpHost implements RegExpLanguageHost {
+  @Override
+  public boolean characterNeedsEscaping(char c) {
+    return c == ']' || c == '}';
+  }
+
+  @Override
+  public boolean supportsPerl5EmbeddedComments() {
+    return false;
+  }
+
+  @Override
+  public boolean supportsPossessiveQuantifiers() {
+    return false;
+  }
+
+  @Override
+  public boolean supportsPythonConditionalRefs() {
+    return false;
+  }
+
+  @Override
+  public boolean supportsNamedGroupSyntax(RegExpGroup group) {
+    if (group.isRubyNamedGroup()) {
+      final Module module = ModuleUtil.findModuleForPsiElement(group);
+      if (module != null) {
+        final Sdk sdk = ModuleRootManager.getInstance(module).getSdk();
+        if (sdk != null && sdk.getSdkType() instanceof JavaSdk) {
+          final JavaSdkVersion version = JavaSdk.getInstance().getVersion(sdk);
+          return version != null && version.isAtLeast(JavaSdkVersion.JDK_1_7);
+        }
+      }
+    }
+    return false;
+  }
+}