oms3.compiler.MemoryOutputJavaFileManager Maven / Gradle / Ivy
package oms3.compiler;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.MalformedURLException;
import java.net.URI;
import java.net.URISyntaxException;
import java.net.URL;
import java.net.URLConnection;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Set;
import javax.tools.FileObject;
import javax.tools.ForwardingJavaFileManager;
import javax.tools.JavaFileManager;
import javax.tools.JavaFileObject;
import javax.tools.StandardLocation;
import javax.tools.JavaFileObject.Kind;
/**
* A java file manager that stores output in memory, delegating all other
* functions to another file manager.
*
*/
public class MemoryOutputJavaFileManager extends ForwardingJavaFileManager {
/**
* Maps class names to file objects.
*/
Map outputMap = new HashMap();
List classPathUrls = new ArrayList();
/**
* Constructs a MemoryOutputJavaFileManager.
*
* @param fileManager the underlying file manager to use.
*/
public MemoryOutputJavaFileManager(JavaFileManager fileManager) {
super(fileManager);
}
/**
* Adds a URL that classes may be loaded from. All classes from this
* URL will be added to the classpath.
*
* @param url the URL to add.
*
* @throws NullPointerException if url is null.
*/
public void addClassPathUrl(URL url) {
if (url == null) {
throw new NullPointerException("url == null");
}
classPathUrls.add(url);
}
/**
* Returns the base URL of the specified class.
*
*
* For example, if java.lang.String exists at
* http://base.net/parent/java/lang/String.class, the base URL
* is http://base.net/parent/.
*
* @param clazz the class.
*
* @return a base URL where the class is located.
*
* @throws IllegalArgumentException if a URL cannot be obtained.
*/
public static URL baseUrlOfClass(Class clazz) {
try {
String name = clazz.getName();
URL url = clazz.getResource("/" + name.replace('.', '/') + ".class");
int curPos = 0;
do {
curPos = name.indexOf('.', curPos + 1);
if (curPos >= 0) {
url = new URL(url, "..");
}
} while (curPos >= 0);
return url;
} catch (MalformedURLException e) {
throw new IllegalArgumentException("Invalid URL for class " + clazz.getName(), e);
}
}
@Override
public JavaFileObject getJavaFileForOutput(Location location, String className, Kind kind, FileObject sibling)
throws IOException {
if (kind != Kind.CLASS) {
throw new IOException("Only class output supported, kind=" + kind);
}
try {
MemoryOutputJavaFileObject output = new MemoryOutputJavaFileObject(new URI(className), kind);
outputMap.put(className, output);
return output;
} catch (URISyntaxException e) {
throw new IOException(e);
}
}
@Override
public JavaFileObject getJavaFileForInput(Location location,
String className, Kind kind) throws IOException {
JavaFileObject result;
if (StandardLocation.CLASS_OUTPUT == location && Kind.CLASS == kind) {
result = outputMap.get(className);
if (result == null) {
result = super.getJavaFileForInput(location, className, kind);
}
} else {
result = super.getJavaFileForInput(location, className, kind);
}
return result;
}
@Override
public String inferBinaryName(Location location, JavaFileObject file) {
if (file instanceof UrlJavaFileObject) {
UrlJavaFileObject urlFile = (UrlJavaFileObject) file;
return urlFile.getBinaryName();
} else {
return super.inferBinaryName(location, file);
}
}
@Override
public Iterable list(Location location, String packageName,
Set kinds, boolean recurse) throws IOException {
//Special handling for Privateer classes when building with Maven
//Maven does not set the classpath but instead uses a custom
//classloader to load test classes which means the compiler
//tool cannot normally see standard Privateer classes so
//we put in a workaround here
if (StandardLocation.CLASS_PATH == location && kinds.contains(Kind.CLASS)) {
List results = new ArrayList();
Iterable superResults = super.list(location, packageName, kinds, recurse);
for (JavaFileObject superResult : superResults) {
results.add(superResult);
}
//Now process classpath URLs
for (URL curClassPathUrl : classPathUrls) {
String directory = packageName.replace('.', '/') + '/';
URL loadUrl = new URL(curClassPathUrl, directory);
try {
List additionalClasses = listClassesFromUrl(loadUrl, packageName);
results.addAll(additionalClasses);
} catch (IOException e) {
//This happens if the file does not exist
//Move onto next one
}
}
return results;
} else {
Iterable results = super.list(location, packageName, kinds, recurse);
return results;
}
}
/**
* Lists all files at a specified URL.
*
* @param base the URL.
* @param packageName the package name of classes to list.
*
* @return a list of class files.
*
* @throws IOException if an I/O error occurs.
*/
protected List listClassesFromUrl(URL base, String packageName) throws IOException {
//TODO this will only work with file:// not jar://
if (base == null) {
throw new NullPointerException("base == null");
}
List list = new ArrayList();
URLConnection connection = base.openConnection();
connection.connect();
String encoding = connection.getContentEncoding();
if (encoding == null) {
encoding = "UTF-8";
}
BufferedReader reader = new BufferedReader(new InputStreamReader(connection.getInputStream(), encoding));
try {
String curLine;
do {
curLine = reader.readLine();
if (curLine != null && curLine.endsWith(".class")) {
try {
String curSimpleName = curLine.substring(0, curLine.length() - ".class".length());
String binaryName;
if (packageName == null) {
binaryName = curSimpleName;
} else {
binaryName = packageName + "." + curSimpleName;
}
list.add(new UrlJavaFileObject(curLine, new URL(base, curLine), Kind.CLASS, binaryName));
} catch (URISyntaxException e) {
throw new IOException("Error parsing URL " + curLine + ".", e);
}
}
} while (curLine != null);
} finally {
reader.close();
}
return list;
}
}