Project: Google Web Toolkit

Revision: 3622

Author: scottb@google.com

Date: 04 Sep 2008 18:38:41

• /trunk/dev/core/src/com/google/gwt/dev/shell/EmmaStrategy.java

  ......	@@ -0,0 +1,88 @@
  	1	/*
  	2	* Copyright 2008 Google Inc.
  	3	*
  	4	* Licensed under the Apache License, Version 2.0 (the "License"); you may not
  	5	* use this file except in compliance with the License. You may obtain a copy of
  	6	* the License at
  	7	*
  	8	* http://www.apache.org/licenses/LICENSE-2.0
  	9	*
  	10	* Unless required by applicable law or agreed to in writing, software
  	11	* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
  	12	* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
  	13	* License for the specific language governing permissions and limitations under
  	14	* the License.
  	15	*/
  	16	package com.google.gwt.dev.shell;
  	17
  	18	import com.google.gwt.dev.util.Util;
  	19
  	20	import java.io.IOException;
  	21	import java.net.URL;
  	22	import java.net.URLConnection;
  	23
  	24	/**
  	25	* Provides various strategies for emma integration based on runtime detection.
  	26	*/
  	27	abstract class EmmaStrategy {
  	28
  	29	private static class NoEmmaStrategy extends EmmaStrategy {
  	30	public byte[] getEmmaClassBytes(byte[] classBytes, String slashedName,
  	31	long unitLastModified) {
  	32	return classBytes;
  	33	}
  	34	}
  	35
  	36	private static class PreinstrumentedEmmaStrategy extends EmmaStrategy {
  	37	public byte[] getEmmaClassBytes(byte[] classBytes, String slashedName,
  	38	long unitLastModified) {
  	39	// Check for an existing class on the classpath.
  	40	URL url = Thread.currentThread().getContextClassLoader().getResource(
  	41	slashedName + ".class");
  	42	if (url != null) {
  	43	// We found it on the class path.
  	44	try {
  	45	URLConnection conn = url.openConnection();
  	46	if (conn.getLastModified() >= unitLastModified) {
  	47	// It's as new as the source file, let's use it.
  	48	byte[] result = Util.readURLConnectionAsBytes(conn);
  	49	if (result != null) {
  	50	return result;
  	51	}
  	52	// Fall through.
  	53	}
  	54	// Fall through.
  	55	} catch (IOException ignored) {
  	56	// Fall through.
  	57	}
  	58	}
  	59
  	60	// Just return what we got.
  	61	return classBytes;
  	62	}
  	63	}
  	64
  	65	/**
  	66	* Classname for Emma's RT, to enable bridging.
  	67	*/
  	68	public static final String EMMA_RT_CLASSNAME = "com.vladium.emma.rt.RT";
  	69
  	70	/**
  	71	* Gets the emma classloading strategy.
  	72	*/
  	73	public static EmmaStrategy get(boolean emmaIsAvailable) {
  	74	/*
  	75	* Theoretically, emmarun could be using an instrumented ClassLoader, but in
  	76	* practice we haven't been able to make GWT run at all in this case.
  	77	*/
  	78	if (!emmaIsAvailable) {
  	79	return new NoEmmaStrategy();
  	80	} else {
  	81	return new PreinstrumentedEmmaStrategy();
  	82	}
  	83	}
  	84
  	85	public abstract byte[] getEmmaClassBytes(byte[] classBytes,
  	86	String slashedName, long unitLastModified);
  	87
  	88	}

• /trunk/dev/core/src/com/google/gwt/dev/util/Util.java

  ......	@@ -599,22 +599,12 @@
  599	599	* @return null if the file could not be read
  600	600	*/
  601	601	public static byte[] readURLAsBytes(URL url) {
  602		// ENH: add a weak cache that has an additional check against the file date
  603		InputStream input = null;
  604	602	try {
  605		URLConnection connection = url.openConnection();
  606		connection.setUseCaches(false);
  607		input = connection.getInputStream();
  608		int contentLength = connection.getContentLength();
  609		if (contentLength < 0) {
  610		return null;
  611		}
  612
  613		return readBytesFromInputStream(input, contentLength);
  	603	URLConnection conn = url.openConnection();
  	604	conn.setUseCaches(false);
  	605	return readURLConnectionAsBytes(conn);
  614	606	} catch (IOException e) {
  615	607	return null;
  616		} finally {
  617		Utility.close(input);
  618	608	}
  619	609	}
  620	610
  ......	@@ -622,7 +612,6 @@
  622	612	* @return null if the file could not be read
  623	613	*/
  624	614	public static char[] readURLAsChars(URL url) {
  625		// ENH: add a weak cache that has an additional check against the file date
  626	615	byte[] bytes = readURLAsBytes(url);
  627	616	if (bytes != null) {
  628	617	return toString(bytes, DEFAULT_ENCODING).toCharArray();
  ......	@@ -631,6 +620,24 @@
  631	620	return null;
  632	621	}
  633	622
  	623	public static byte[] readURLConnectionAsBytes(URLConnection connection) {
  	624	// ENH: add a weak cache that has an additional check against the file date
  	625	InputStream input = null;
  	626	try {
  	627	input = connection.getInputStream();
  	628	int contentLength = connection.getContentLength();
  	629	if (contentLength < 0) {
  	630	return null;
  	631	}
  	632
  	633	return readBytesFromInputStream(input, contentLength);
  	634	} catch (IOException e) {
  	635	return null;
  	636	} finally {
  	637	Utility.close(input);
  	638	}
  	639	}
  	640
  634	641	/**
  635	642	* Deletes a file or recursively deletes a directory.
  636	643	*

• /trunk/dev/core/src/com/google/gwt/dev/shell/CompilingClassLoader.java

  ......	@@ -354,10 +354,25 @@
  354	354	*/
  355	355	private static byte[] javaScriptHostBytes;
  356	356
  	357	private static EmmaStrategy emmaStrategy;
  	358
  357	359	static {
  358	360	for (Class<?> c : BRIDGE_CLASSES) {
  359	361	BRIDGE_CLASS_NAMES.put(c.getName(), c);
  360	362	}
  	363	/*
  	364	* Specific support for bridging to Emma since the user classloader is
  	365	* generally completely isolated.
  	366	*/
  	367	boolean emmaIsAvailable = false;
  	368	try {
  	369	Class<?> emmaBridge = Class.forName(EmmaStrategy.EMMA_RT_CLASSNAME,
  	370	false, Thread.currentThread().getContextClassLoader());
  	371	BRIDGE_CLASS_NAMES.put(EmmaStrategy.EMMA_RT_CLASSNAME, emmaBridge);
  	372	emmaIsAvailable = true;
  	373	} catch (ClassNotFoundException ignored) {
  	374	}
  	375	emmaStrategy = EmmaStrategy.get(emmaIsAvailable);
  361	376	}
  362	377
  363	378	private static void classDump(String name, byte[] bytes) {
  ......	@@ -637,6 +652,8 @@
  637	652	injectJsniFor(compiledClass);
  638	653
  639	654	byte[] classBytes = compiledClass.getBytes();
  	655	classBytes = emmaStrategy.getEmmaClassBytes(classBytes, lookupClassName,
  	656	compiledClass.getUnit().getLastModified());
  640	657	if (classRewriter != null) {
  641	658	byte[] newBytes = classRewriter.rewrite(className, classBytes);
  642	659	if (CLASS_DUMP) {