Mercurial > jdk8-mips64-public > nashorn / file revision

 #// Usage: jjs -fx javaastviewer.js -- <.java files>

 /*

  * Copyright (c) 2014, 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.

  */

 // This example demonstrates Java subclassing by Java.extend

 // and javac Compiler and Tree API. This example also uses

 // -fx and javafx TreeView to visualize Java AST as TreeView

 if (!$OPTIONS._fx || arguments.length == 0) {

     print("Usage: jjs -fx javaastviewer.js -- <.java files>");

     exit(1);

 }

 // Java types used

 var Enum = Java.type("java.lang.Enum");

 var HashSet  = Java.type("java.util.HashSet");

 var Name = Java.type("javax.lang.model.element.Name");

 var List = Java.type("java.util.List");

 var Set  = Java.type("java.util.Set");

 var SimpleTreeVisitor = Java.type("com.sun.source.util.SimpleTreeVisitor");

 var StringArray = Java.type("java.lang.String[]");

 var ToolProvider = Java.type("javax.tools.ToolProvider");

 var Tree = Java.type("com.sun.source.tree.Tree");

 function javaASTToScriptObject(args) {

     // properties ignored (javac implementation class properties) in AST view.

     // may not be exhaustive - any getAbc would become "abc" property or

     // public field becomes a property of same name.

     var ignoredProps = new HashSet();

     for each (var word in 

         ['extending', 'implementing', 'init', 'mods', 'clazz', 'defs', 

          'expr', 'tag', 'preferredPosition', 'qualid', 'recvparam',

          'restype', 'params', 'startPosition', 'thrown',

          'tree', 'typarams', 'typetag', 'vartype']) {

         ignoredProps.add(word);

     }

     // get the system compiler tool

     var compiler = ToolProvider.systemJavaCompiler;

     // get standard file manager

     var fileMgr = compiler.getStandardFileManager(null, null, null);

     // make a list of compilation unit from command line argument file names

     // Using Java.to convert script array (arguments) to a Java String[]

     var compUnits = fileMgr.getJavaFileObjects(Java.to(args, StringArray));

     // create a new compilation task

     var task = compiler.getTask(null, fileMgr, null, null, null, compUnits);

     // subclass SimpleTreeVisitor - converts Java AST node to

     // a simple script object by walking through it

     var ConverterVisitor = Java.extend(SimpleTreeVisitor);

     var visitor = new ConverterVisitor() {

         // convert java AST node to a friendly script object

         // which can be viewed. Every node ends up in defaultAction 

         // method of SimpleTreeVisitor method.

         defaultAction: function (node, p) {

             var resultObj = {};

             // Nashorn does not iterate properties and methods of Java objects

             // But, we can bind properties of any object (including java objects)

             // to a script object and iterate it!

             var obj = {};

             Object.bindProperties(obj, node);

             // we don't want every property, method of java object

             for (var prop in obj) {

                 var val = obj[prop];

                 var type = typeof val;

                 // ignore 'method' members

                 if (type == 'function' || type == 'undefined') {

                     continue;

                 }

                 // ignore properties from Javac implementation

                 // classes - hack by name!!

                 if (ignoredProps.contains(prop)) {

                     continue;

                 }

                 // subtree - recurse it

                 if (val instanceof Tree) {

                     resultObj[prop] = visitor.visit(val, p);

                 } else if (val instanceof List) {

                     // List of trees - recurse each and make an array

                     var len = val.size();

                     if (len != 0) {

                         var arr = [];

                         for (var j = 0; j < len; j++) {

                             var e = val[j];

                             if (e instanceof Tree) {

                                 arr.push(visitor.visit(e, p));

                             }

                         }

                         resultObj[prop] = arr;

                     }

                 } else if (val instanceof Set) {

                     // Set - used for modifier flags

                     // make array

                     var len = val.size();

                     if (len != 0) {

                         var arr = [];

                         for each (var e in val) {

                             if (e instanceof Enum || typeof e == 'string') {

                                 arr.push(e.toString());

                             }

                         }

                         resultObj[prop] = arr;

                     }

                 } else if (val instanceof Enum || val instanceof Name) {

                     // make string for any Enum or Name

                     resultObj[prop] = val.toString();

                 } else if (type != 'object') {

                     // primitives 'as is'

                     resultObj[prop] = val;

                 }

             }

             return resultObj;

         }

     }

     // top level object with one property for each compilation unit

     var scriptObj = {};

     for each (var cu in task.parse()) {

         scriptObj[cu.sourceFile.name] = cu.accept(visitor, null);

     }

     return scriptObj;

 }

 // JavaFX classes used

 var StackPane = Java.type("javafx.scene.layout.StackPane");

 var Scene     = Java.type("javafx.scene.Scene");

 var TreeItem  = Java.type("javafx.scene.control.TreeItem");

 var TreeView  = Java.type("javafx.scene.control.TreeView");

 // Create a javafx TreeItem to view a script object

 function treeItemForObject(obj, name) {

     var item = new TreeItem(name);

     for (var prop in obj) {

        var node = obj[prop];

        if (typeof node == 'object') {

            if (node == null) {

                // skip nulls

                continue;

            }

            var subitem = treeItemForObject(node, prop);

        } else {

            var subitem = new TreeItem(prop + ": " + node);

        }

        item.children.add(subitem);

     }

     item.expanded = true;

     return item;

 }

 var commandArgs = arguments;

 // JavaFX start method

 function start(stage) {

     var obj = javaASTToScriptObject(commandArgs);

     stage.title = "Java AST Viewer"

     var rootItem = treeItemForObject(obj, "AST");

     rootItem.expanded = true;

     var tree = new TreeView(rootItem);

     var root = new StackPane();

     root.children.add(tree);

     stage.scene = new Scene(root, 300, 450);

     stage.show();

 }