/*
* 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.LinkerOrder;
import com.google.gwt.core.ext.linker.LinkerOrder.Order;
import com.google.gwt.core.ext.linker.Shardable;
import com.google.gwt.core.ext.linker.impl.SelectionScriptLinker;
import com.google.gwt.dev.About;
import com.google.gwt.dev.util.DefaultTextOutput;
/**
* Implements the canonical GWT bootstrap sequence that loads the GWT module in
* a separate iframe.
*/
@LinkerOrder(Order.PRIMARY)
@Shardable
public class IFrameLinker extends SelectionScriptLinker {
/**
* This string is inserted between script chunks. It is made default access
* for testing.
*/
static final String SCRIPT_CHUNK_SEPARATOR = "--></script>\n<script><!--\n";
@Override
public String getDescription() {
return "Standard";
}
@Override
protected String getCompilationExtension(TreeLogger logger,
LinkerContext context) {
return ".cache.html";
}
@Override
protected String getHostedFilename() {
return "hosted.html";
}
@Override
protected String getModulePrefix(TreeLogger logger, LinkerContext context,
String strongName) throws UnableToCompleteException {
return getModulePrefix(logger, context, strongName, true);
}
@Override
protected String getModulePrefix(TreeLogger logger, LinkerContext context,
String strongName, int numFragments) throws UnableToCompleteException {
return getModulePrefix(logger, context, strongName, numFragments > 1);
}
@Override
protected String getModuleSuffix(TreeLogger logger, LinkerContext context) {
DefaultTextOutput out = new DefaultTextOutput(context.isOutputCompact());
out.print("$stats && $stats({moduleName:'" + context.getModuleName()
+ "',sessionId:$sessionId"
+ ",subSystem:'startup',evtGroup:'moduleStartup'"
+ ",millis:(new Date()).getTime(),type:'moduleEvalEnd'});");
// Generate the call to tell the bootstrap code that we're ready to go.
out.newlineOpt();
out.print("if ($wnd." + context.getModuleFunctionName() + ") $wnd."
+ context.getModuleFunctionName() + ".onScriptLoad();");
out.newline();
out.print("--></script></body></html>");
out.newlineOpt();
return out.toString();
}
@Override
protected String getScriptChunkSeparator(TreeLogger logger, LinkerContext context) {
return SCRIPT_CHUNK_SEPARATOR;
}
@Override
protected String getSelectionScriptTemplate(TreeLogger logger, LinkerContext context) {
return "com/google/gwt/core/linker/IFrameTemplate.js";
}
protected String modifyPrimaryJavaScript(String js) {
return js;
}
/**
* This is the real implementation of <code>getModulePrefix</code> for this
* linker. The other versions forward to this one.
*/
private String getModulePrefix(TreeLogger logger, LinkerContext context,
String strongName, boolean supportRunAsync)
throws UnableToCompleteException {
DefaultTextOutput out = new DefaultTextOutput(context.isOutputCompact());
out.print("<html>");
out.newlineOpt();
// Setup the well-known variables.
out.print("<head><meta charset=\"UTF-8\" /><script>");
out.newlineOpt();
out.print("var $gwt_version = \"" + About.getGwtVersionNum() + "\";");
out.newlineOpt();
out.print("var $wnd = parent;");
out.newlineOpt();
out.print("var $doc = $wnd.document;");
out.newlineOpt();
out.print("var $moduleName, $moduleBase;");
out.newlineOpt();
out.print("var $strongName = '" + strongName + "';");
out.newlineOpt();
if (supportRunAsync) {
out.print("function __gwtStartLoadingFragment(frag) {");
out.indentIn();
out.newlineOpt();
out.print(" return $moduleBase + '" + getFragmentSubdir(logger, context)
+ "/' + $strongName + '/' + frag + '" + FRAGMENT_EXTENSION + "';");
out.indentOut();
out.newlineOpt();
out.print("};");
out.newlineOpt();
out.print("function __gwtInstallCode(code) {");
/*
* Use a script tag on all platforms, for simplicity. It would be cleaner
* to use window.eval, but at the time of writing that only reliably works
* on Firefox. It would also be cleaner to use window.execScript on
* platforms that support it (IE and Chrome). However, trying this causes
* IE 6 (and possibly others) to emit "error 80020101", apparently due to
* something objectionable in the compiler's output JavaScript.
*/
out.indentIn();
out.newlineOpt();
out.print("var head = document.getElementsByTagName('head').item(0);");
out.newlineOpt();
out.print("var script = document.createElement('script');");
out.newlineOpt();
out.print("script.type = 'text/javascript';");
out.newlineOpt();
out.print("script.text = code;");
out.newlineOpt();
out.print("head.appendChild(script);");
out.indentOut();
out.newlineOpt();
out.print("};");
out.newlineOpt();
}
out.print("var $stats = $wnd.__gwtStatsEvent ? function(a) {return $wnd.__gwtStatsEvent(a);} : null,");
out.newlineOpt();
out.print("$sessionId = $wnd.__gwtStatsSessionId ? $wnd.__gwtStatsSessionId : null;");
out.newlineOpt();
out.print("$stats && $stats({moduleName:'" + context.getModuleName()
+ "',sessionId:$sessionId"
+ ",subSystem:'startup',evtGroup:'moduleStartup'"
+ ",millis:(new Date()).getTime(),type:'moduleEvalStart'});");
out.newlineOpt();
out.print("</script></head>");
out.newlineOpt();
out.print("<body>");
out.newlineOpt();
// Begin a script block inside the body. It's commented out so that the
// browser won't mistake strings containing "<script>" for actual script.
out.print("<script><!--");
out.newline();
return out.toString();
}
}