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#// 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();
}
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