Lang EP for psi <--> String conversions

platform/lang-api/src/com/intellij/lang/LanguagePsiElementExternalizer.java

@@ -0,0 +1,43 @@
+/*
+ * Copyright 2000-2014 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.lang;
+
+import com.intellij.openapi.project.Project;
+import com.intellij.psi.PsiElement;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+/**
+ * @author Konstantin Bulenkov
+ */
+public class LanguagePsiElementExternalizer extends LanguageExtension<PsiElementExternalizer> {
+  public static final LanguagePsiElementExternalizer INSTANCE = new LanguagePsiElementExternalizer();
+
+  private LanguagePsiElementExternalizer() {
+    super("com.intellij.lang.psiElementExternalizer", new PsiElementExternalizer() {
+      @Override
+      public String getQualifiedName(PsiElement element) {
+        return null;
+      }
+
+      @Nullable
+      @Override
+      public PsiElement findByQualifiedName(Project project, @NotNull String qualifiedName) {
+        return null;
+      }
+    });
+  }
+}

platform/lang-api/src/com/intellij/lang/PsiElementExternalizer.java

@@ -0,0 +1,31 @@
+/*
+ * Copyright 2000-2014 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.lang;
+
+import com.intellij.openapi.project.Project;
+import com.intellij.psi.PsiElement;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+/**
+ * @author Konstantin Bulenkov
+ */
+public interface PsiElementExternalizer {
+  String getQualifiedName(PsiElement element);
+
+  @Nullable
+  PsiElement findByQualifiedName(Project project, @NotNull String qualifiedName);
+}

platform/platform-resources/src/META-INF/LangExtensionPoints.xml

@@ -164,6 +164,11 @@
       <with attribute="implementationClass" implements="com.intellij.lang.PsiStructureViewFactory"/>
     </extensionPoint>
 
+    <extensionPoint name="lang.psiElementExternalizer"
+                    beanClass="com.intellij.lang.LanguageExtensionPoint">
+      <with attribute="implementationClass" implements="com.intellij.lang.PsiElementExternalizer"/>
+    </extensionPoint>
+
     <extensionPoint name="lang.structureViewExtension"
                     interface="com.intellij.ide.structureView.StructureViewExtension"/>