org.codehaus.janino

Class JavaSourceClassLoader

java.lang.Object

java.lang.ClassLoader

org.codehaus.commons.compiler.AbstractJavaSourceClassLoader

org.codehaus.janino.JavaSourceClassLoader

Direct Known Subclasses:

CachingJavaSourceClassLoader

public class JavaSourceClassLoader
extends AbstractJavaSourceClassLoader

A ClassLoader that, unlike usual ClassLoaders, does not load byte code, but reads Java source code and then scans, parses, compiles and loads it into the virtual machine.

As with any ClassLoader, it is not possible to "update" classes after they've been loaded. The way to achieve this is to give up on the JavaSourceClassLoader and create a new one.

Nested Class Summary

Nested classes/interfaces inherited from class org.codehaus.commons.compiler.AbstractJavaSourceClassLoader

AbstractJavaSourceClassLoader.ProtectionDomainFactory

Field Summary

Fields inherited from class org.codehaus.commons.compiler.AbstractJavaSourceClassLoader

optionalProtectionDomainFactory

Constructor Summary

Constructors

Constructor and Description
JavaSourceClassLoader()
JavaSourceClassLoader(ClassLoader parentClassLoader)
JavaSourceClassLoader(ClassLoader parentClassLoader, File[] optionalSourcePath, String optionalCharacterEncoding) Sets up a JavaSourceClassLoader that finds Java source code in a file that resides in either of the directories specified by the given source path.
JavaSourceClassLoader(ClassLoader parentClassLoader, JavaSourceIClassLoader iClassLoader) Constructs a JavaSourceClassLoader that finds classes through an JavaSourceIClassLoader.
JavaSourceClassLoader(ClassLoader parentClassLoader, ResourceFinder sourceFinder, String optionalCharacterEncoding) Constructs a JavaSourceClassLoader that finds Java source code through a given ResourceFinder.

Method Summary

Modifier and Type	Method and Description
protected Class<?>	findClass(String name) Implementation of ClassLoader.findClass(String).
protected Map<String,byte[]>	generateBytecodes(String name) Finds, scans, parses the right compilation unit.
void	setCompileErrorHandler(ErrorHandler optionalCompileErrorHandler)
void	setDebuggingInfo(boolean debugSource, boolean debugLines, boolean debugVars)
void	setSourceFileCharacterEncoding(String optionalCharacterEncoding)
void	setSourcePath(File[] sourcePath)
void	setWarningHandler(WarningHandler optionalWarningHandler)

Methods inherited from class org.codehaus.commons.compiler.AbstractJavaSourceClassLoader

main, setProtectionDomainFactory

Methods inherited from class java.lang.ClassLoader

clearAssertionStatus, defineClass, defineClass, defineClass, defineClass, definePackage, findLibrary, findLoadedClass, findResource, findResources, findSystemClass, getClassLoadingLock, getPackage, getPackages, getParent, getResource, getResourceAsStream, getResources, getSystemClassLoader, getSystemResource, getSystemResourceAsStream, getSystemResources, loadClass, loadClass, registerAsParallelCapable, resolveClass, setClassAssertionStatus, setDefaultAssertionStatus, setPackageAssertionStatus, setSigners

Methods inherited from class java.lang.Object

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

Constructor Detail

JavaSourceClassLoader

public JavaSourceClassLoader()

JavaSourceClassLoader

public JavaSourceClassLoader(ClassLoader parentClassLoader)

JavaSourceClassLoader

public JavaSourceClassLoader(ClassLoader parentClassLoader,
                             @Nullable
                             File[] optionalSourcePath,
                             @Nullable
                             String optionalCharacterEncoding)

Sets up a JavaSourceClassLoader that finds Java source code in a file that resides in either of the directories specified by the given source path.

Parameters:

parentClassLoader - See ClassLoader

optionalSourcePath - A collection of directories that are searched for Java source files in the given order

optionalCharacterEncoding - The encoding of the Java source files (null for platform default encoding)

JavaSourceClassLoader

public JavaSourceClassLoader(ClassLoader parentClassLoader,
                             ResourceFinder sourceFinder,
                             @Nullable
                             String optionalCharacterEncoding)

Constructs a JavaSourceClassLoader that finds Java source code through a given ResourceFinder.

You can specify to include certain debugging information in the generated class files, which is useful if you want to debug through the generated classes (see Scanner.Scanner(String, Reader)).

Parameters:

parentClassLoader - See ClassLoader

sourceFinder - Used to locate additional source files

optionalCharacterEncoding - The encoding of the Java source files (null for platform default encoding)

JavaSourceClassLoader

public JavaSourceClassLoader(ClassLoader parentClassLoader,
                             JavaSourceIClassLoader iClassLoader)

Constructs a JavaSourceClassLoader that finds classes through an JavaSourceIClassLoader.

Method Detail

setSourcePath

public void setSourcePath(File[] sourcePath)

Specified by:

setSourcePath in class AbstractJavaSourceClassLoader

Parameters:

sourcePath - The sequence of directories to search for Java source files

setSourceFileCharacterEncoding

public void setSourceFileCharacterEncoding(@Nullable
                                           String optionalCharacterEncoding)

Specified by:

setSourceFileCharacterEncoding in class AbstractJavaSourceClassLoader

Parameters:

optionalCharacterEncoding - if null, use platform default encoding

setDebuggingInfo

public void setDebuggingInfo(boolean debugSource,
                             boolean debugLines,
                             boolean debugVars)

Specified by:

setDebuggingInfo in class AbstractJavaSourceClassLoader

Parameters:

debugSource - Whether line number debugging information should be generated

debugLines - Whether variables debugging information should be generated

debugVars - Whether source file debugging information should be generated

setCompileErrorHandler

public void setCompileErrorHandler(@Nullable
                                   ErrorHandler optionalCompileErrorHandler)

See Also:

UnitCompiler.setCompileErrorHandler(org.codehaus.commons.compiler.ErrorHandler)

setWarningHandler

public void setWarningHandler(@Nullable
                              WarningHandler optionalWarningHandler)

See Also:

Parser.setWarningHandler(WarningHandler), UnitCompiler.setCompileErrorHandler(org.codehaus.commons.compiler.ErrorHandler)

findClass

protected Class<?> findClass(@Nullable
                             String name)
                      throws ClassNotFoundException

Implementation of ClassLoader.findClass(String).

Overrides:

findClass in class ClassLoader

Throws:

ClassNotFoundException

generateBytecodes

@Nullable
protected Map<String,byte[]> generateBytecodes(String name)
                                                   throws ClassNotFoundException

Finds, scans, parses the right compilation unit. Compile the parsed compilation unit to bytecode. This may cause more compilation units being scanned and parsed. Continue until all compilation units are compiled.

Returns:

String name => byte[] bytecode, or null if no source code could be found

Throws:

ClassNotFoundException - on compilation problems