com.feedzai.openml.java.utils

Class JavaFileUtils

java.lang.Object

com.feedzai.openml.java.utils.JavaFileUtils

public class JavaFileUtils
extends Object

Contains the common utility methods used by OpenML providers to interact with Java files.

Author:

Paulo Pereira (paulo.pereira@feedzai.com)

Since:

0.1.0

Field Summary

Fields

Modifier and Type	Field and Description
static String	JAR_EXTENSION Extension of jar files.
static String	JAVA_FILE_EXTENSION Extension of Java files.

Method Summary

Modifier and Type	Method and Description
static boolean	cleanUnnecessaryFiles(Path exportDir) Deletes unnecessary files from the given directory.
static void	compileJavaFile(JavaCompiler compiler, String javaFile) Compiles the java file specified by the given Path.
static JarOutputStream	createJar(Path directory, String filename) Creates a new empty jar.
static Object	createNewInstanceFromClassLoader(String modelPath, String simpleNameFormat, URLClassLoader urlClassLoader) Loads a class from a URLClassLoader and creates new instance of that class.
static URLClassLoader	getUrlClassLoader(String modelPath, ClassLoader classLoader) Gets a URLClassLoader used to retrieve an instance of class that contains the model.
static JavaCompiler	initCompiler() Initializes the compiler using the ToolProvider API.
static boolean	isJarFile(String filePath) Verifies that the filePath received by parameter is equals to the extension of a Jar file.
static boolean	writeClassesToJar(Path exportDir, JarOutputStream jar) Writes the existing .class files on the directory into the jar file.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

JAR_EXTENSION

public static final String JAR_EXTENSION

Extension of jar files.

See Also:

Constant Field Values

JAVA_FILE_EXTENSION

public static final String JAVA_FILE_EXTENSION

Extension of Java files.

See Also:

Constant Field Values

Method Detail

getUrlClassLoader

public static URLClassLoader getUrlClassLoader(String modelPath,
                                               ClassLoader classLoader)
                                        throws com.feedzai.openml.provider.exception.ModelLoadingException

Gets a URLClassLoader used to retrieve an instance of class that contains the model.

Parameters:

modelPath - Path of the binary with the model.

Returns:

a URLClassLoader used to retrieve an instanece of the model.

Throws:

com.feedzai.openml.provider.exception.ModelLoadingException - If it cannot get the path of the model.

createNewInstanceFromClassLoader

public static Object createNewInstanceFromClassLoader(String modelPath,
                                                      String simpleNameFormat,
                                                      URLClassLoader urlClassLoader)
                                               throws com.feedzai.openml.provider.exception.ModelLoadingException

Loads a class from a URLClassLoader and creates new instance of that class.

Parameters:

modelPath - Path of the binary with the model.

simpleNameFormat - Format of the class/package of the instance to create.

urlClassLoader - The URLClassLoader used to retrieve an instance of the model.

Returns:

The new instance of the loaded class.

Throws:

com.feedzai.openml.provider.exception.ModelLoadingException - If it cannot create the instance.

isJarFile

public static boolean isJarFile(String filePath)

Verifies that the filePath received by parameter is equals to the extension of a Jar file.

Parameters:

filePath - The path of the file to be verified.

Returns:

True if it has the Jar file, false otherwise.

initCompiler

public static JavaCompiler initCompiler()

Initializes the compiler using the ToolProvider API.

Returns:

A new instance of a JavaCompiler.

compileJavaFile

public static void compileJavaFile(JavaCompiler compiler,
                                   String javaFile)

Compiles the java file specified by the given Path.

Parameters:

javaFile - The Path of the java file.

createJar

public static JarOutputStream createJar(Path directory,
                                        String filename)
                                 throws IOException

Creates a new empty jar.

Parameters:

directory - The directory where to create the jar file.

filename - The name of the jar file without the extension.

Returns:

The new empty jar file.

Throws:

IOException - If any problem occurs accessing the file system.

writeClassesToJar

public static boolean writeClassesToJar(Path exportDir,
                                        JarOutputStream jar)

Writes the existing .class files on the directory into the jar file.

Parameters:

exportDir - The directory containing the .class files

jar - The jar to save the files to.

Returns:

A boolean indicating whether the operation was successful or not.

cleanUnnecessaryFiles

public static boolean cleanUnnecessaryFiles(Path exportDir)

Deletes unnecessary files from the given directory.

Parameters:

exportDir - The directory to clean.

Returns:

A boolean indicating whether the operation was successful or not.