Libraries: adding sources swithces all open class files with java files.

java/java-impl/src/com/intellij/codeEditor/JavaEditorFileSwapper.java

@@ -0,0 +1,54 @@
+/*
+ * Copyright 2000-2010 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.codeEditor;
+
+import com.intellij.openapi.fileEditor.impl.EditorFileSwapper;
+import com.intellij.openapi.project.Project;
+import com.intellij.openapi.vfs.VirtualFile;
+import com.intellij.psi.*;
+import com.intellij.psi.impl.compiled.ClsClassImpl;
+import com.intellij.psi.impl.compiled.ClsFileImpl;
+import com.intellij.psi.search.GlobalSearchScope;
+
+public class JavaEditorFileSwapper implements EditorFileSwapper {
+  public VirtualFile getFileToSwapTo(Project project, VirtualFile original) {
+    return findSourceFile(project, original);
+  }
+
+  public static VirtualFile findSourceFile(Project project, VirtualFile eachFile) {
+    PsiFile psiFile = PsiManager.getInstance(project).findFile(eachFile);
+    if (!(psiFile instanceof ClsFileImpl)) return null;
+
+    PsiClass clsClass = JavaPsiFacade.getInstance(project).findClass(getFQN(psiFile), GlobalSearchScope.allScope(project));
+    if (!(clsClass instanceof ClsClassImpl)) return null;
+
+    PsiClass sourceClass = ((ClsClassImpl)clsClass).getSourceMirrorClass();
+    if (sourceClass == null || sourceClass == clsClass) return null;
+
+    VirtualFile result = sourceClass.getContainingFile().getVirtualFile();
+    assert result != null;
+    return result;
+  }
+
+  public static String getFQN(PsiFile psiFile) {
+    if (!(psiFile instanceof PsiJavaFile)) return null;
+    PsiClass[] classes = ((PsiJavaFile)psiFile).getClasses();
+    if (classes.length == 0) return null;
+    final String fqn = classes[0].getQualifiedName();
+    if (fqn == null) return null;
+    return fqn;
+  }
+}