// Copyright 2011 Benjamin McCann. All Rights Reserved.
package com.benmccann.closure;
import java.io.File;
import java.io.IOException;
import java.io.OutputStream;
import java.io.PrintStream;
import java.util.List;
import com.google.common.base.Strings;
import com.google.common.collect.Lists;
import com.google.javascript.jscomp.CommandLineRunner;
import com.google.javascript.jscomp.Compiler;
import com.google.javascript.jscomp.CompilerOptions;
import com.google.javascript.jscomp.JSError;
import com.google.javascript.jscomp.JSSourceFile;
import com.google.javascript.jscomp.Result;
/**
* Invokes the Closure compiler.
*
* @author Ben McCann (benmccann.com)
*/
public class CompilerInvoker {
private final List<File> inputFiles;
private final List<File> externFiles;
private final List<String> entryPoints;
private final CompilerOptions compilerOptions;
public CompilerInvoker(
List<File> inputFiles,
List<File> externFiles,
List<String> entryPoints,
CompilerOptions compilerOptions) {
this.inputFiles = inputFiles;
this.externFiles = externFiles;
this.entryPoints = entryPoints;
this.compilerOptions = compilerOptions;
}
public void compile(OutputStream outputStream)
throws IOException, JavascriptCompilationException {
PrintStream printStream = new PrintStream(outputStream);
Compiler compiler = new Compiler(System.err);
List<JSSourceFile> inputs = filesToJsSourceFiles(inputFiles);
List<JSSourceFile> externs = CommandLineRunner.getDefaultExterns();
externs.addAll(filesToJsSourceFiles(externFiles));
compilerOptions.setManageClosureDependencies(entryPoints);
Result result = compiler.compile(externs, inputs, compilerOptions);
if (result.success) {
printStream.println(compiler.toSource());
} else {
for (JSError error : result.errors) {
printError(printStream, "ERROR", error);
}
for (JSError warning : result.warnings) {
printError(printStream, "WARNING", warning);
}
printStream.println();
printStream.println(result.errors.length + " error(s), " + result.warnings.length + " warning(s)");
throw new JavascriptCompilationException("Error during JavaScript compilation");
}
}
private void printError(PrintStream printStream, String level, JSError error) {
printStream.println((!Strings.isNullOrEmpty(error.sourceName) ? error.sourceName : "(unknown source)")
+ ":" + (error.lineNumber != -1 ? String.valueOf(error.lineNumber) : "(unknown line)")
+ ": " + level + " - " + error.description);
}
private List<JSSourceFile> filesToJsSourceFiles(List<File> inputFiles) {
List<JSSourceFile> inputs = Lists.newArrayList();
for (File file : inputFiles) {
inputs.add(JSSourceFile.fromFile(file));
}
return inputs;
}
public static class JavascriptCompilationException extends Exception {
private static final long serialVersionUID = 1L;
public JavascriptCompilationException(String message) {
super(message);
}
}
}