prevent static field name clashes in local methods

src/org/jetbrains/java/decompiler/util/StructUtils.java

@@ -0,0 +1,65 @@
+/*
+ * Copyright 2000-2016 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 org.jetbrains.java.decompiler.util;
+
+import org.jetbrains.java.decompiler.main.DecompilerContext;
+import org.jetbrains.java.decompiler.main.rels.MethodWrapper;
+import org.jetbrains.java.decompiler.struct.StructMember;
+import org.jetbrains.java.decompiler.struct.attr.StructGeneralAttribute;
+import org.jetbrains.java.decompiler.struct.attr.StructLocalVariableTableAttribute;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+
+import static org.jetbrains.java.decompiler.main.DecompilerContext.CURRENT_METHOD_WRAPPER;
+import static org.jetbrains.java.decompiler.struct.attr.StructGeneralAttribute.ATTRIBUTE_LOCAL_VARIABLE_TABLE;
+
+/**
+ * @author Alexandru-Constantin Bledea
+ * @since March 07, 2016
+ */
+public final class StructUtils {
+
+  private StructUtils() {
+  }
+
+  /**
+   * @return the local variables of the current method
+   */
+  public static List<String> getCurrentMethodLocalVariableNames() {
+    final MethodWrapper method = (MethodWrapper) DecompilerContext.getProperty(CURRENT_METHOD_WRAPPER);
+    if (null == method) {
+      return Collections.emptyList();
+    }
+    return getLocalVariables(method.methodStruct);
+  }
+
+  /**
+   * @param structMember the struct member from which to extract the local variables
+   * @return the local variables of the struct member
+   */
+  public static List<String> getLocalVariables(final StructMember structMember) {
+    final VBStyleCollection<StructGeneralAttribute, String> methodStruct = structMember.getAttributes();
+    final StructGeneralAttribute generalAttribute = methodStruct.getWithKey(ATTRIBUTE_LOCAL_VARIABLE_TABLE);
+    if (generalAttribute instanceof StructLocalVariableTableAttribute) {
+      final StructLocalVariableTableAttribute table = (StructLocalVariableTableAttribute) generalAttribute;
+      return Collections.unmodifiableList(new ArrayList<>(table.getMapVarNames().values()));
+    }
+    return Collections.emptyList();
+  }
+
+}