alma.acs.classloading.JarOrderOptimizer Class Reference

Inherits java::util::Comparator< File >.

List of all members.

Public Member Functions
int	compare (File f1, File f2)
Static Public Attributes
static final String	PROPERTY_APPLICATION_TOPJARS = "acs.system.classpath.appltopjars"
static final String[]	orderedAcsJarNames
Package Functions
	JarOrderOptimizer (boolean verbose)
void	sortJars (List< File > jarlist)
List< File >	getTopJarsOnly (List< File > allJars)
boolean	isClassKnownToBeUnavailable (String name)

---

Detailed Description

Helps sort a list of jar files so that more important jar files appear first. The more important jar files are listed in orderedAcsJarNames and optionally also in the property acs.system.classpath.appltopjars.

The classloader will then not have to read through unimportant jar files first, which should improve class loading performance on IO-challenged machines.

Author:

hsommer created Sep 21, 2004 2:28:51 PM

---

Constructor & Destructor Documentation

alma.acs.classloading.JarOrderOptimizer.JarOrderOptimizer

(

boolean

verbose

)

[package]

References alma.acs.classloading.JarOrderOptimizer.orderedAcsJarNames, and alma.acs.classloading.JarOrderOptimizer.PROPERTY_APPLICATION_TOPJARS.

---

Member Function Documentation

int alma.acs.classloading.JarOrderOptimizer.compare	(	File	f1,
		File	f2
	)

List<File> alma.acs.classloading.JarOrderOptimizer.getTopJarsOnly

(

List< File >

allJars

)

[package]

To be used for testing only -- allows to filter out all jar files from a list which are not given priority by the compare method of this class. This allows to write tests that will fail unless all required classes are listed explicitly.

Parameters:

allJars

jar files to be filtered

Returns:

those whose name matches one from the prio list

boolean alma.acs.classloading.JarOrderOptimizer.isClassKnownToBeUnavailable

(

String

name

)

[package]

Checks if a class comes from any of the subpackages of sun. or com.sun. which we strongly assume to not be contained in any jar files that our classloaders have to deal with. These classes should either be loaded by the real system class loader, and when it fails, we assume that they don't exist anywhere so we can skip searching for them.

Parameters:

name

Returns:

Referenced by alma.acs.classloading.AcsSystemClassLoader.findClass().

void alma.acs.classloading.JarOrderOptimizer.sortJars

(

List< File >

jarlist

)

[package]

Sorts jars using compare(Object, Object).

See also:

Arrays.sort(java.lang.Object[], java.util.Comparator)

---

Member Data Documentation

final String [] alma.acs.classloading.JarOrderOptimizer.orderedAcsJarNames [static]

Hardcoded list of jar files that are sufficient to start an ACS container or other basic ACS software. The class loader will sort these jar files toward the beginning of the classpath (in the given order), and will append jar files from the optional property acs.system.classpath.appltopjars.

Referenced by alma.acs.classloading.JarOrderOptimizer.JarOrderOptimizer().

final String alma.acs.classloading.JarOrderOptimizer.PROPERTY_APPLICATION_TOPJARS = "acs.system.classpath.appltopjars" [static]

Referenced by alma.acs.classloading.JarOrderOptimizer.JarOrderOptimizer().

---

The documentation for this class was generated from the following file:

• JarOrderOptimizer.java