/*
* Copyright 2008 Google Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License"); you may not
* use this file except in compliance with the License. You may obtain a copy of
* the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations under
* the License.
*/
package com.google.gwt.core.linker;
import com.google.gwt.core.ext.LinkerContext;
import com.google.gwt.core.ext.TreeLogger;
import com.google.gwt.core.ext.UnableToCompleteException;
import com.google.gwt.core.ext.linker.ArtifactSet;
import com.google.gwt.core.ext.linker.CompilationResult;
import com.google.gwt.core.ext.linker.EmittedArtifact;
import com.google.gwt.core.ext.linker.LinkerOrder;
import com.google.gwt.core.ext.linker.LinkerOrder.Order;
import com.google.gwt.core.ext.linker.impl.SelectionScriptLinker;
import com.google.gwt.dev.About;
import com.google.gwt.dev.util.DefaultTextOutput;
import java.util.Collection;
import java.util.Set;
/**
* A Linker for producing a single JavaScript file from a GWT module. The use of
* this Linker requires that the module has exactly one distinct compilation
* result.
*/
@LinkerOrder(Order.PRIMARY)
public class SingleScriptLinker extends SelectionScriptLinker {
@Override
public String getDescription() {
return "Single Script";
}
@Override
public ArtifactSet link(TreeLogger logger, LinkerContext context,
ArtifactSet artifacts) throws UnableToCompleteException {
ArtifactSet toReturn = new ArtifactSet(artifacts);
toReturn.add(emitSelectionScript(logger, context, artifacts));
return toReturn;
}
@Override
protected Collection<EmittedArtifact> doEmitCompilation(TreeLogger logger,
LinkerContext context, CompilationResult result)
throws UnableToCompleteException {
if (result.getJavaScript().length != 1) {
logger.branch(TreeLogger.ERROR,
"The module must not have multiple fragments when using the "
+ getDescription() + " Linker.", null);
throw new UnableToCompleteException();
}
return super.doEmitCompilation(logger, context, result);
}
@Override
protected EmittedArtifact emitSelectionScript(TreeLogger logger,
LinkerContext context, ArtifactSet artifacts)
throws UnableToCompleteException {
DefaultTextOutput out = new DefaultTextOutput(true);
// Emit the selection script.
String bootstrap = generateSelectionScript(logger, context, artifacts);
bootstrap = context.optimizeJavaScript(logger, bootstrap);
out.print(bootstrap);
out.newlineOpt();
// Emit the module's JS a closure.
out.print("(function () {");
out.newlineOpt();
out.print("var $gwt_version = \"" + About.getGwtVersionNum() + "\";");
out.newlineOpt();
out.print("var $wnd = window;");
out.newlineOpt();
out.print("var $doc = $wnd.document;");
out.newlineOpt();
out.print("var $moduleName, $moduleBase;");
out.newlineOpt();
out.print("var $stats = $wnd.__gwtStatsEvent ? function(a) {$wnd.__gwtStatsEvent(a)} : null;");
out.newlineOpt();
// Find the single CompilationResult
Set<CompilationResult> results = artifacts.find(CompilationResult.class);
if (results.size() != 1) {
logger.log(TreeLogger.ERROR,
"The module must have exactly one distinct"
+ " permutation when using the " + getDescription() + " Linker.",
null);
throw new UnableToCompleteException();
}
CompilationResult result = results.iterator().next();
out.print("var $strongName = '" + result.getStrongName() + "';");
out.newlineOpt();
String[] js = result.getJavaScript();
if (js.length != 1) {
logger.log(TreeLogger.ERROR,
"The module must not have multiple fragments when using the "
+ getDescription() + " Linker.", null);
throw new UnableToCompleteException();
}
out.print(js[0]);
// Generate the call to tell the bootstrap code that we're ready to go.
out.newlineOpt();
out.print("if (" + context.getModuleFunctionName() + ") "
+ context.getModuleFunctionName() + ".onScriptLoad(gwtOnLoad);");
out.newlineOpt();
out.print("})();");
out.newlineOpt();
return emitString(logger, out.toString(), context.getModuleName()
+ ".nocache.js");
}
/**
* Unimplemented. Normally required by
* {@link #doEmitCompilation(TreeLogger, LinkerContext, CompilationResult)}.
*/
@Override
protected String getCompilationExtension(TreeLogger logger,
LinkerContext context) throws UnableToCompleteException {
throw new UnableToCompleteException();
}
/**
* Unimplemented. Normally required by
* {@link #doEmitCompilation(TreeLogger, LinkerContext, CompilationResult)}.
*/
@Override
protected String getModulePrefix(TreeLogger logger, LinkerContext context,
String strongName) throws UnableToCompleteException {
throw new UnableToCompleteException();
}
/**
* Unimplemented. Normally required by
* {@link #doEmitCompilation(TreeLogger, LinkerContext, CompilationResult)}.
*/
@Override
protected String getModuleSuffix(TreeLogger logger, LinkerContext context)
throws UnableToCompleteException {
throw new UnableToCompleteException();
}
@Override
protected String getSelectionScriptTemplate(TreeLogger logger,
LinkerContext context) throws UnableToCompleteException {
return "com/google/gwt/core/linker/SingleScriptTemplate.js";
}
}