com.mysema.codegen.SimpleCompiler Maven / Gradle / Ivy

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/*
 * Copyright (c) 2010 Mysema Ltd.
 * All rights reserved.
 * 
 */
package com.mysema.codegen;

import java.io.File;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.UnsupportedEncodingException;
import java.io.Writer;
import java.net.URL;
import java.net.URLClassLoader;
import java.net.URLDecoder;
import java.nio.charset.Charset;
import java.util.ArrayList;
import java.util.List;
import java.util.Locale;
import java.util.Set;

import javax.lang.model.SourceVersion;
import javax.tools.DiagnosticListener;
import javax.tools.JavaCompiler;
import javax.tools.JavaFileManager;
import javax.tools.JavaFileObject;
import javax.tools.StandardJavaFileManager;
import javax.tools.ToolProvider;

/**
 * SimpleCompiler provides a convenience wrapper of the JavaCompiler interface
 * with automatic classpath generation
 * 
 * @author tiwe
 * 
 */
public class SimpleCompiler implements JavaCompiler {

    public static String getClassPath(URLClassLoader classLoader) {
        try {
            StringBuilder path = new StringBuilder();
            for (URL url : ((URLClassLoader) classLoader).getURLs()) {
                if (path.length() > 0) {
                    path.append(File.pathSeparator);
                }
                String decodedPath = URLDecoder.decode(url.getPath(), "UTF-8");
                path.append(new File(decodedPath).getAbsolutePath());
            }
            return path.toString();
        } catch (UnsupportedEncodingException e) {
            throw new CodegenException(e);
        }
    }

    private final ClassLoader classLoader;

    private String classPath;

    private final JavaCompiler compiler;

    public SimpleCompiler() {
        this(ToolProvider.getSystemJavaCompiler(), Thread.currentThread().getContextClassLoader());
    }

    public SimpleCompiler(JavaCompiler compiler, ClassLoader classLoader) {
        this.compiler = compiler;
        this.classLoader = classLoader;
    }

    private String getClasspath() {
        if (classPath == null) {
            if (classLoader instanceof URLClassLoader) {
                classPath = getClassPath((URLClassLoader) classLoader);
            } else {
                throw new IllegalArgumentException("Unsupported ClassLoader " + classLoader);
            }
        }
        return classPath;
    }

    @Override
    public Set getSourceVersions() {
        return compiler.getSourceVersions();
    }

    @Override
    public StandardJavaFileManager getStandardFileManager(
            DiagnosticListener diagnosticListener, Locale locale,
            Charset charset) {
        return compiler.getStandardFileManager(diagnosticListener, locale, charset);
    }

    @Override
    public CompilationTask getTask(Writer out, JavaFileManager fileManager,
            DiagnosticListener diagnosticListener,
            Iterable options, Iterable classes,
            Iterable compilationUnits) {
        return compiler.getTask(out, fileManager, diagnosticListener, options, classes,
                compilationUnits);
    }

    @Override
    public int isSupportedOption(String option) {
        return compiler.isSupportedOption(option);
    }

    @Override
    public int run(InputStream in, OutputStream out, OutputStream err, String... arguments) {
        for (String a : arguments) {
            if (a.equals("-classpath")) {
                return compiler.run(in, out, err, arguments);
            }
        }

        // no classpath given
        List args = new ArrayList(arguments.length + 2);
        args.add("-classpath");
        args.add(getClasspath());
        for (String arg : arguments) {
            args.add(arg);
        }
        return compiler.run(in, out, err, args.toArray(new String[args.size()]));
    }

}