text: /*
   * Copyright (c) 2015, Oracle and/or its affiliates. All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   *
   *   - Redistributions of source code must retain the above copyright
   *     notice, this list of conditions and the following disclaimer.
   *
   *   - Redistributions in binary form must reproduce the above copyright
   *     notice, this list of conditions and the following disclaimer in the
   *     documentation and/or other materials provided with the distribution.
   *
   *   - Neither the name of Oracle nor the names of its
   *     contributors may be used to endorse or promote products derived
   *     from this software without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
   * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
   * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
   * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR
   * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
   * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
   * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
   * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
   * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
   * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
   * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   */
  
  // Usage: jjs find_underscores.js -- <directory>
  
  if (arguments.length == 0) {
      print("Usage: jjs find_underscores.js -- <directory>");
      exit(1);
  }
  
  // Java types used
  var File = Java.type("java.io.File");
  var Files = Java.type("java.nio.file.Files");
  var StringArray = Java.type("java.lang.String[]");
  var ToolProvider = Java.type("javax.tools.ToolProvider");
  var Tree = Java.type("com.sun.source.tree.Tree");
  var Trees = Java.type("com.sun.source.util.Trees");
  var TreeScanner = Java.type("com.sun.source.util.TreeScanner");
  
  function findUnderscores() {
      // get the system compiler tool
      var compiler = ToolProvider.systemJavaCompiler;
      // get standard file manager
      var fileMgr = compiler.getStandardFileManager(null, null, null);
      // Using Java.to convert script array (arguments) to a Java String[]
      var compUnits = fileMgr.getJavaFileObjects(Java.to(arguments, StringArray));
      // create a new compilation task
      var task = compiler.getTask(null, fileMgr, null, null, null, compUnits);
      var sourcePositions = Trees.instance(task).sourcePositions;
      // subclass SimpleTreeVisitor - to find underscore variable names
      var UnderscoreFinder = Java.extend(TreeScanner);
  
      var visitor = new UnderscoreFinder() {
          // override to capture information on current compilation unit
          visitCompilationUnit: function(compUnit, p) {
              this.compUnit = compUnit;
              this.lineMap = compUnit.lineMap;
              this.fileName = compUnit.sourceFile.name;
  
              return Java.super(visitor).visitCompilationUnit(compUnit, p);
          },
  
          // override to check variable name
          visitVariable: function(node, p) {
              if (node.name.toString() == "_") {
                  var pos = sourcePositions.getStartPosition(this.compUnit, node);
                  var line = this.lineMap.getLineNumber(pos);
                  var col = this.lineMap.getColumnNumber(pos);
                  print(node + " @ " + this.fileName + ":" + line + ":" + col);
              }
  
              return Java.super(visitor).visitVariable(node, p);
          }
      }
  
      for each (var cu in task.parse()) {
          cu.accept(visitor, null);
      }
  }
  
  // for each ".java" file in directory (recursively).
  function main(dir) {
      var totalCount = 0;
      Files.walk(dir.toPath()).
        forEach(function(p) {
            var name = p.toFile().absolutePath;
            if (name.endsWith(".java")) {
                findUnderscores(p);
            }
        });
  }
  
  main(new File(arguments[0]));
  