io.toolisticon.cute.JavaFileObjectUtils Maven / Gradle / Ivy
package io.toolisticon.cute;
import io.toolisticon.cute.impl.CommonUtilities;
import javax.tools.SimpleJavaFileObject;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.Reader;
import java.io.StringBufferInputStream;
import java.net.URI;
import java.net.URISyntaxException;
import java.net.URL;
import java.util.ArrayList;
import java.util.List;
/**
* Utility class to create JavaFileObjects and therefore also FileObjects.
* These files can be used for comparision or as source files during compilation.
*/
public class JavaFileObjectUtils {
/**
* A file object used to represent source coming from a string.
*/
public static class JavaSourceFromString extends SimpleJavaFileObject {
/**
* The source content of this "file".
*/
private final String content;
/**
* Constructs a new JavaSourceFromString.
*
* @param name the name of the compilation unit represented by this file object
* @param content the source content for the compilation unit represented by this file object
*/
private JavaSourceFromString(String name, String content) {
super(URI.create("string://" + name.replace('.', '/') + Kind.SOURCE.extension),
Kind.SOURCE);
this.content = content;
}
@Override
public InputStream openInputStream() throws IOException {
return new StringBufferInputStream(this.content);
}
@Override
public Reader openReader(boolean ignoreEncodingErrors) throws IOException {
return new InputStreamReader(openInputStream());
}
@Override
public CharSequence getCharContent(boolean ignoreEncodingErrors) {
return content;
}
}
/**
* Resource based java source.
*/
public static class JavaSourceFromResource extends SimpleJavaFileObject {
private final static String JAVA_COMPATIBILTY_FILE_ENDING_SUFFIX = ".ct";
private final Class relativeLocationRoot;
private final String location;
private JavaSourceFromResource(String location) {
this(location, null);
}
private JavaSourceFromResource(String location, Class relativeLocationRoot) {
super(URI.create("resource://" + (location.endsWith(".java" + JAVA_COMPATIBILTY_FILE_ENDING_SUFFIX) ? location.substring(0, location.length() - JAVA_COMPATIBILTY_FILE_ENDING_SUFFIX.length()) : location)), Kind.SOURCE);
this.relativeLocationRoot = relativeLocationRoot;
this.location = location;
}
@Override
public InputStream openInputStream() throws IOException {
Class relativeRoot = relativeLocationRoot != null ? relativeLocationRoot : JavaFileObjectUtils.class;
InputStream inputStream = relativeRoot.getResourceAsStream(location);
if (inputStream == null) {
throw new IllegalStateException(Constants.Messages.ISE_CANNOT_OPEN_INPUTSTREAM_WITH_URI.produceMessage(uri.toString()));
}
return inputStream;
}
@Override
public Reader openReader(boolean ignoreEncodingErrors) throws IOException {
return new InputStreamReader(openInputStream());
}
@Override
public CharSequence getCharContent(boolean ignoreEncodingErrors) throws IOException {
return readFromInputStream(openInputStream());
}
}
/**
* Url based java source.
*/
public static class JavaSourceFromUrl extends SimpleJavaFileObject {
private final URL url;
private JavaSourceFromUrl(URL url) throws URISyntaxException {
super(url.toURI(), Kind.SOURCE);
this.url = url;
}
@Override
public InputStream openInputStream() throws IOException {
return url.openStream();
}
@Override
public Reader openReader(boolean ignoreEncodingErrors) throws IOException {
return new InputStreamReader(openInputStream());
}
@Override
public CharSequence getCharContent(boolean ignoreEncodingErrors) throws IOException {
return readFromInputStream(openInputStream());
}
}
/**
* Read a java source file from resources.
*
* Some IDEs like Eclipse don't like resource files ending with *.java.
* In this case extend the file name by ".ct" suffix (f.e. "JavaClass.java.ct").
* The suffix will be ignored for looking up files via the compile test file manager.
* *
*
* @param location the location
* @param relativeLocationRoot relative location root class
* @return The SimpleJavaFileObject for resource
*/
public static SimpleJavaFileObject readFromResource(String location, Class relativeLocationRoot) {
if (location == null) {
throw new IllegalArgumentException(Constants.Messages.IAE_PASSED_PARAMETER_MUST_NOT_BE_NULL.produceMessage("location"));
}
return new JavaSourceFromResource(location, relativeLocationRoot);
}
/**
* Read a java source file from resources.
* Passed location will be handled as absolute path and will be used to both read resource and as location in compile test file manager.
*
* Some IDEs like Eclipse don't like resource files ending with *.java.
* In this case extend the file name by ".ct" suffix (f.e. "JavaClass.java.ct").
* The suffix will be ignored for looking up files via the compile test file manager.
*
* @param location the location
* @return The SimpleJavaFileObject for resource
*/
public static SimpleJavaFileObject readFromResource(String location) {
if (location == null) {
throw new IllegalArgumentException(Constants.Messages.IAE_PASSED_PARAMETER_MUST_NOT_BE_NULL.produceMessage("location"));
}
return new JavaSourceFromResource((!location.startsWith("/") ? "/" : "") + location, null);
}
/**
* Reads multiple java source files from resources.
* Passed locations will be handled as absolute path and will be used to both read resource and as location in compile test file manager.
*
* Some IDEs like Eclipse don't like resource files ending with *.java.
* In this case extend the file name by ".ct" suffix (f.e. "JavaClass.java.ct").
* The suffix will be ignored for looking up files via the compile test file manager.
*
* @param locations the location
* @return The SimpleJavaFileObject for resource
*/
public static SimpleJavaFileObject[] readFromResources(String... locations) {
List resourceFiles = new ArrayList();
for (String location : locations) {
resourceFiles.add(readFromResource(location));
}
return resourceFiles.toArray(new SimpleJavaFileObject[resourceFiles.size()]);
}
/**
* Read a java source file from string.
*
* @param location the location
* @param content content of the file
* @return The SimpleJavaFileObject for passed content string
*/
public static SimpleJavaFileObject readFromString(String location, String content) {
if (location == null) {
throw new IllegalArgumentException(Constants.Messages.IAE_PASSED_PARAMETER_MUST_NOT_BE_NULL.produceMessage("location"));
}
if (content == null) {
throw new IllegalArgumentException(Constants.Messages.IAE_PASSED_PARAMETER_MUST_NOT_BE_NULL.produceMessage("content"));
}
return new JavaSourceFromString(location, content);
}
/**
* Read a java source file from resources.
* This one works great if you don't rely on the location, f.e. in case of comparision.
*
* @param content content of the file
* @return he SimpleJavaFileObject for passed content string
*/
public static SimpleJavaFileObject readFromString(String content) {
// create a random location
String location = "string_" + CommonUtilities.getRandomString(6);
return readFromString(location, content);
}
/**
* Read a java source file from resurces.
*
* @param url the location
* @return The SimpleJavaFileObject for passed URL
* @throws URISyntaxException if passed url cannot be converted into URI
* @throws IllegalArgumentException if passed url is null
*/
public static SimpleJavaFileObject readFromUrl(URL url) throws URISyntaxException {
if (url == null) {
throw new IllegalArgumentException(Constants.Messages.IAE_PASSED_PARAMETER_MUST_NOT_BE_NULL.produceMessage("url"));
}
return new JavaSourceFromUrl(url);
}
/**
* Reads a String from an InputStream.
* CLoses the stream
*
* @param stream the inputStream to use
* @return The String read from the inputStreams
* @throws IOException if an error occurs
*/
private static String readFromInputStream(InputStream stream) throws IOException {
byte[] buffer = new byte[10000];
ByteArrayOutputStream os = new ByteArrayOutputStream();
int line = 0;
// read bytes from stream, and store them in buffer
while ((line = stream.read(buffer)) != -1) {
// Writes bytes from byte array (buffer) into output stream.
os.write(buffer, 0, line);
}
stream.close();
os.flush();
os.close();
return new String(os.toByteArray());
}
}