Java example source code file (logcoverage.js)

This example Java source code file (logcoverage.js) is included in the alvinalexander.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

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Java - Java tags/keywords

bytearrayoutputstream, javaimporter, nashornscriptenginefactory, printstream

The logcoverage.js Java example source code

/*
 * Copyright (c) 2010, 2013, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 * 
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 * 
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 * 
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 * 
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

/**
 * mh_coverage.js
 * Screen scrape various logs to ensure that we cover enough functionality, 
 * e.g. method handle instrumentation
 *
 * @test
 * @run
 */

/*
 * creates new script engine initialized with given options and
 * runs given code on it. Returns standard output captured.
 */

function runScriptEngine(opts, name) {
    var imports = new JavaImporter(
        Packages.jdk.nashorn.api.scripting,
        java.io, java.lang, java.util);

    with(imports) {
        var fac = new NashornScriptEngineFactory();
        // get current System.err
        var oldErr = System.err;
	var oldOut = System.out;
        var baosErr = new ByteArrayOutputStream();
        var newErr = new PrintStream(baosErr);
        var baosOut = new ByteArrayOutputStream();
	var newOut = new PrintStream(baosOut);
        try {
            // set new standard err
            System.setErr(newErr);
            System.setOut(newOut);
            var engine = fac.getScriptEngine(Java.to(opts, "java.lang.String[]"));
	    var reader = new java.io.FileReader(name);
            engine.eval(reader);
            newErr.flush();
	    newOut.flush();
            return new java.lang.String(baosErr.toByteArray());
        } finally {
            // restore System.err to old value
            System.setErr(oldErr);
	    System.setOut(oldOut);
        }
    }
}

var str;

var methodsCalled = [
   'asCollector', 
   'asType', 
   'bindTo', 
   'dropArguments', 
   'explicitCastArguments', 
   'filterArguments', 
   'filterReturnValue', 
   'findStatic', 
   'findVirtual',  
   'foldArguments', 
   'getter', 
   'guardWithTest', 
   'insertArguments', 
   'methodType', 
   'setter'
];

function check(str, strs) {
    for each (s in strs) {
       if (str.indexOf(s) !== -1) {
	   continue;
       }
       print(s + " not found");
       return;
    }
    print("check ok!");
}

str = runScriptEngine([ "--log=codegen,compiler=finest,methodhandles=finest,fields=finest" ], __DIR__ + "../basic/NASHORN-19.js");
str += runScriptEngine([ "--log=codegen,compiler=finest,methodhandles=finest,fields=finest" ], __DIR__ + "../basic/varargs.js");

check(str, methodsCalled);
check(str, ['return', 'get', 'set', '[fields]']);
check(str, ['codegen']);

print("hello, world!");