--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/nashorn/samples/resourcetrysuggester.js Mon Sep 14 16:13:10 2015 +0530
@@ -0,0 +1,156 @@
+#// Usage: jjs resourcetrysuggester.js -- <directory>
+
+/*
+ * 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.
+ */
+
+// This example demonstrates Java subclassing by Java.extend
+// and javac Compiler and Tree API. This example looks for
+// finally clauses with "close" call and suggests "resource try"!
+
+if (arguments.length == 0) {
+ print("Usage: jjs resourcetrysuggester.js -- <directory>");
+ exit(1);
+}
+
+// Java types used
+var ExpressionStatementTree = Java.type("com.sun.source.tree.ExpressionStatementTree");
+var File = Java.type("java.io.File");
+var Files = Java.type("java.nio.file.Files");
+var MemberSelectTree = Java.type("com.sun.source.tree.MemberSelectTree");
+var MethodInvocationTree = Java.type("com.sun.source.tree.MethodInvocationTree");
+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");
+
+// resourceTrySuggestions
+
+function resourceTrySuggestions() {
+ // 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);
+
+ // SourcePositions object to get positions of AST nodes
+ var sourcePositions = Trees.instance(task).sourcePositions;
+
+ // subclass SimpleTreeVisitor - to print resource try suggestions
+ var ResourceTrySuggester = Java.extend(TreeScanner);
+
+ function hasOnlyEmptyStats(stats) {
+ var itr = stats.iterator();
+ while (itr.hasNext()) {
+ if (! (itr.next() instanceof EmptyStatementTree)) {
+ return false;
+ }
+ }
+
+ return true;
+ }
+
+ // does the given statement list has an expression statement which
+ // calls "close" method (don't worry about types - just crude one will do)
+ function hasCloseCall(stats) {
+ var itr = stats.iterator();
+ while (itr.hasNext()) {
+ var stat = itr.next();
+ if (stat instanceof ExpressionStatementTree) {
+ var expr = stat.expression;
+ if (expr instanceof MethodInvocationTree) {
+ var method = expr.methodSelect;
+ if (method instanceof MemberSelectTree) {
+ return method.identifier.toString().equals("close");
+ }
+ }
+ }
+ }
+ return false;
+ }
+
+ var visitor = new ResourceTrySuggester() {
+ // current CompilationUnitTree
+ compUnit: null,
+ // current LineMap (pos -> line, column)
+ lineMap: null,
+ // current compilation unit's file name
+ fileName: null,
+
+ // overrides of TreeScanner methods
+
+ visitCompilationUnit: function(node, p) {
+ // capture info about current Compilation unit
+ this.compUnit = node;
+ this.lineMap = node.lineMap;
+ this.fileName = node.sourceFile.name;
+
+ // Using Java.super API to call super class method here
+ return Java.super(visitor).visitCompilationUnit(node, p);
+ },
+
+ visitTry: function (node, p) {
+ var finallyBlk = node.finallyBlock;
+ if (finallyBlk != null && hasCloseCall(finallyBlk.statements)) {
+ var pos = sourcePositions.getStartPosition(this.compUnit, node);
+ var line = this.lineMap.getLineNumber(pos);
+ var col = this.lineMap.getColumnNumber(pos);
+ print("Consider resource try statement " + " @ " + this.fileName + ":" + line + ":" + col);
+ // print(node);
+ }
+ }
+ }
+
+ for each (var cu in task.parse()) {
+ cu.accept(visitor, null);
+ }
+}
+
+// for each ".java" file in directory (recursively) and check it!
+function main(dir) {
+ Files.walk(dir.toPath()).
+ forEach(function(p) {
+ var name = p.toFile().absolutePath;
+ if (name.endsWith(".java")) {
+ try {
+ resourceTrySuggestions(p.toFile().getAbsolutePath());
+ } catch (e) {
+ print(e);
+ }
+ }
+ });
+}
+
+main(new File(arguments[0]));