org.mule.util.scan
Class ClasspathScanner

java.lang.Object
  org.mule.util.scan.ClasspathScanner

public class ClasspathScanner
extends Object

This class can be used to scan the classpath for classtypes (or interfaces they implement) or for annotations on the classpath. The type of scanner used depends on the class type passed in. There are currently 3 types of scanner;

• InterfaceClassScanner - will search for all class that are assignable to the interface provided
• ImplementationClassScanner - will search for all classes that extend a base type
• AnnotationsScanner - will search for classes with specific annotations, this can also seach for meta annotations

This scanner uses ASM to search class byte code rather than the classes themselves making orders of magnitude better performance and uses a lot less memory. ASM seems to be the fasted of the byte code manipulation libraries i.e. JavaAssist or BCEL Note that the scanner will not scan inner or anonymous classes.

Field Summary

static int	DEFAULT_FLAGS
static int	INCLUDE_ABSTRACT
static int	INCLUDE_ANONYMOUS
static int	INCLUDE_INNER
static int	INCLUDE_INTERFACE
protected Log	logger logger used by this class

Constructor Summary

ClasspathScanner(ClassLoader classLoader, String... basepaths)

ClasspathScanner(String... basepaths)

Method Summary

protected <T> void	addClassToSet(Class<T> c, Set<Class<T>> set, int flags)
protected ClassScanner	getScanner(Class<?> clazz) Works out the correct scanner based on the class passed in Note that these could be better architected by breaking out filters into strategy objects, but for now this suits my needs
protected boolean	hasFlag(int flags, int flag)
protected Class<?>	loadClass(String name)
protected <T> Set<Class<T>>	processFileUrl(URL url, String basepath, Class<T> clazz, int flags)
protected <T> Set<Class<T>>	processJarUrl(URL url, String basepath, Class<T> clazz, int flags)
<T> Set<Class<T>>	scanFor(Class<T> clazz)
<T> Set<Class<T>>	scanFor(Class<T> clazz, int flags)

Methods inherited from class java.lang.Object

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

Field Detail

INCLUDE_ABSTRACT

public static final int INCLUDE_ABSTRACT

See Also:

Constant Field Values

INCLUDE_INTERFACE

public static final int INCLUDE_INTERFACE

See Also:

Constant Field Values

INCLUDE_INNER

public static final int INCLUDE_INNER

See Also:

Constant Field Values

INCLUDE_ANONYMOUS

public static final int INCLUDE_ANONYMOUS

See Also:

Constant Field Values

DEFAULT_FLAGS

public static final int DEFAULT_FLAGS

See Also:

Constant Field Values

logger

protected final transient Log logger

logger used by this class

Constructor Detail

ClasspathScanner

public ClasspathScanner(String... basepaths)

ClasspathScanner

public ClasspathScanner(ClassLoader classLoader,
                        String... basepaths)

Method Detail

scanFor

public <T> Set<Class<T>> scanFor(Class<T> clazz)
                      throws IOException

Throws:

IOException

scanFor

public <T> Set<Class<T>> scanFor(Class<T> clazz,
                                 int flags)
                      throws IOException

Throws:

IOException

processJarUrl

protected <T> Set<Class<T>> processJarUrl(URL url,
                                          String basepath,
                                          Class<T> clazz,
                                          int flags)
                               throws IOException

Throws:

IOException

hasFlag

protected boolean hasFlag(int flags,
                          int flag)

processFileUrl

protected <T> Set<Class<T>> processFileUrl(URL url,
                                           String basepath,
                                           Class<T> clazz,
                                           int flags)
                                throws IOException

Throws:

IOException

addClassToSet

protected <T> void addClassToSet(Class<T> c,
                                 Set<Class<T>> set,
                                 int flags)

loadClass

protected Class<?> loadClass(String name)

getScanner

protected ClassScanner getScanner(Class<?> clazz)

Works out the correct scanner based on the class passed in

Note that these could be better architected by breaking out filters into strategy objects, but for now this suits my needs

Parameters:

clazz - the type to scan for

Returns:

a scanner suitable for handling the type passed in

See Also:

AnnotationsScanner, InterfaceClassScanner, ImplementationClassScanner