java.lang.Object
- io.microsphere.util.ClassLoaderUtils

All Implemented Interfaces:

Utils
```
public abstract class ClassLoaderUtils
extends java.lang.Object
implements Utils
```
ClassLoader Utility

Since:

1.0.0

Author:

Mercy

See Also:

ClassLoader

Nested Class Summary

Nested Classes
Modifier and Type Class Description

static class ClassLoaderUtils.ResourceType
Resource Type

Field Summary

Fields
Modifier and Type Field Description

protected static java.lang.management.ClassLoadingMXBean classLoadingMXBean

Method Summary

All Methods Static Methods Concrete Methods
Modifier and Type Method Description

protected static java.lang.Class<?> doLoadClass(java.lang.ClassLoader classLoader, java.lang.String className)

static java.util.Set<java.net.URL> findAllClassPathURLs(java.lang.ClassLoader classLoader)

static java.lang.Class<?> findLoadedClass(java.lang.ClassLoader classLoader, java.lang.String className)
Find Loaded Class under specified inheritable ClassLoader

static java.util.Set<java.lang.Class<?>> findLoadedClasses(java.lang.ClassLoader classLoader, java.lang.Iterable<java.lang.String> classNames)
Find Loaded Class under specified inheritable ClassLoader and class names

static java.util.Set<java.lang.Class<?>> findLoadedClasses(java.lang.ClassLoader classLoader, java.lang.String... classNames)
Find Loaded Class under specified inheritable ClassLoader and class names

static java.util.Set<java.lang.Class<?>> findLoadedClassesInClassPath(java.lang.ClassLoader classLoader)
Find loaded classes Set in class path

static java.util.Set<java.lang.Class<?>> findLoadedClassesInClassPath(java.lang.ClassLoader classLoader, java.lang.String classPath)
Find loaded classes Set in class path

static java.util.Set<java.lang.Class<?>> findLoadedClassesInClassPaths(java.lang.ClassLoader classLoader, java.util.Set<java.lang.String> classPaths)
Find loaded classes Set in class paths Set

static java.net.URLClassLoader findURLClassLoader(java.lang.ClassLoader classLoader)

static java.util.Set<java.lang.Class<?>> getAllLoadedClasses(java.lang.ClassLoader classLoader)
Get all loaded classes Set under specified inheritable ClassLoader

static java.util.Map<java.lang.ClassLoader,java.util.Set<java.lang.Class<?>>> getAllLoadedClassesMap(java.lang.ClassLoader classLoader)
Get all loaded classes Map under specified inheritable ClassLoader , ClassLoader as key , its loaded classes Set as value.

static java.lang.ClassLoader getCallerClassLoader()
Return the ClassLoader from the caller class

static java.lang.ClassLoader getClassLoader(java.lang.Class<?> loadedClass)
Get the ClassLoader from the loaded class if present.

static java.net.URL getClassResource(java.lang.Class<?> type)
Get the Class resource URL under specified Class

static java.net.URL getClassResource(java.lang.ClassLoader classLoader, java.lang.Class<?> type)
Get the Class resource URL under specified Class

static java.net.URL getClassResource(java.lang.ClassLoader classLoader, java.lang.String className)
Get the Class resource URL under specified Class name

static java.lang.ClassLoader getDefaultClassLoader()
Get the default the ClassLoader to use.

static java.util.Set<java.lang.ClassLoader> getInheritableClassLoaders(java.lang.ClassLoader classLoader)
Get all Inheritable ClassLoaders Set (including ClassLoader argument)

static int getLoadedClassCount()
Returns the number of classes that are currently loaded in the Java virtual machine.

static java.util.Set<java.lang.Class<?>> getLoadedClasses(java.lang.ClassLoader classLoader)
Get loaded classes Set under specified ClassLoader( not all inheritable ClassLoaders)

static java.net.URL getResource(java.lang.ClassLoader classLoader, ClassLoaderUtils.ResourceType resourceType, java.lang.String resourceName)
Get the resource URL under specified resource name and type

static java.net.URL getResource(java.lang.ClassLoader classLoader, java.lang.String resourceName)
Get the resource URL under specified resource name

static java.net.URL getResource(java.lang.String resourceName)
Get the resource URL under specified resource name

static java.lang.String getResourceAsString(java.lang.ClassLoader classLoader, java.lang.String resourceName)
Get the content of the specified resource as a String.

static java.lang.String getResourceAsString(java.lang.String resourceName)
Get the content of the specified resource as a String.

static java.util.Set<java.net.URL> getResources(java.lang.ClassLoader classLoader, ClassLoaderUtils.ResourceType resourceType, java.lang.String resourceName)
Get the resource URLs Set under specified resource name and type

static java.util.Set<java.net.URL> getResources(java.lang.ClassLoader classLoader, java.lang.String resourceName)
Get the resource URLs list under specified resource name

static long getTotalLoadedClassCount()
Returns the total number of classes that have been loaded since the Java virtual machine has started execution.

static long getUnloadedClassCount()
Returns the total number of classes unloaded since the Java virtual machine has started execution.

static boolean isLoadedClass(java.lang.ClassLoader classLoader, java.lang.Class<?> type)
Check specified Class is loaded on specified inheritable ClassLoader

static boolean isLoadedClass(java.lang.ClassLoader classLoader, java.lang.String className)
Check specified class name is loaded on specified inheritable ClassLoader

static boolean isPresent(java.lang.String className)
Test the specified class name is present in the default ClassLoader

static boolean isPresent(java.lang.String className, java.lang.ClassLoader classLoader)
Test the specified class name is present in the ClassLoader

static boolean isVerbose()
Tests if the verbose output for the class loading system is enabled.

static java.lang.Class<?> loadClass(java.lang.ClassLoader classLoader, java.lang.String className)
Loaded specified class name under ClassLoader

static java.lang.Class<?> loadClass(java.lang.ClassLoader classLoader, java.lang.String className, boolean cached)
Loaded specified class name under ClassLoader

static java.net.URLClassLoader newURLClassLoader(java.lang.Iterable<java.net.URL> urls)
Create a new instance of URLClassLoader

static java.net.URLClassLoader newURLClassLoader(java.lang.Iterable<java.net.URL> urls, java.lang.ClassLoader classLoader)
Create a new instance of URLClassLoader

static java.net.URLClassLoader newURLClassLoader(java.net.URL[] urls)
Create a new instance of URLClassLoader

static java.net.URLClassLoader newURLClassLoader(java.net.URL[] urls, boolean initializedLoaders)
Create a new instance of URLClassLoader

static java.net.URLClassLoader newURLClassLoader(java.net.URL[] urls, java.lang.ClassLoader parent)
Create a new instance of URLClassLoader

static java.net.URLClassLoader newURLClassLoader(java.net.URL[] urls, java.lang.ClassLoader parent, boolean initializedLoaders)
Create a new instance of URLClassLoader

static boolean removeClassPathURL(java.lang.ClassLoader classLoader, java.net.URL url)

static java.lang.Class<?> resolveClass(java.lang.String className)
Resolve the Class by the specified name in the default ClassLoader

static java.lang.Class<?> resolveClass(java.lang.String className, java.lang.ClassLoader classLoader)
Resolve the Class by the specified name and ClassLoader

static java.lang.Class<?> resolveClass(java.lang.String className, java.lang.ClassLoader classLoader, boolean cached)
Resolve the Class by the specified name and ClassLoader

static java.net.URLClassLoader resolveURLClassLoader(java.lang.ClassLoader classLoader)
Try to find the instance of URLClassLoader from the specified ClassLoader, if it can't be found, it will try to find all the URL of class-paths from the specified ClassLoader, and then new a instance of URLClassLoader upon those urls.

static void setVerbose(boolean value)
Enables or disables the verbose output for the class loading system.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

classLoadingMXBean

protected static final java.lang.management.ClassLoadingMXBean classLoadingMXBean

Method Detail

getLoadedClassCount
```
public static int getLoadedClassCount()
```
Returns the number of classes that are currently loaded in the Java virtual machine.

Returns:

the number of currently loaded classes.

getUnloadedClassCount
```
public static long getUnloadedClassCount()
```
Returns the total number of classes unloaded since the Java virtual machine has started execution.

Returns:

the total number of unloaded classes.

getTotalLoadedClassCount
```
public static long getTotalLoadedClassCount()
```
Returns the total number of classes that have been loaded since the Java virtual machine has started execution.

Returns:

the total number of classes loaded.

isVerbose
```
public static boolean isVerbose()
```
Tests if the verbose output for the class loading system is enabled.

Returns:

true if the verbose output for the class loading system is enabled; false otherwise.

setVerbose
```
public static void setVerbose(boolean value)
```
Enables or disables the verbose output for the class loading system. The verbose output information and the output stream to which the verbose information is emitted are implementation dependent. Typically, a Java virtual machine implementation prints a message each time a class file is loaded.

This method can be called by multiple threads concurrently. Each invocation of this method enables or disables the verbose output globally.

Parameters:

value - true to enable the verbose output; false to disable.

Throws:

java.lang.SecurityException - if a security manager exists and the caller does not have ManagementPermission("control").

getDefaultClassLoader
```
@Nullable
public static java.lang.ClassLoader getDefaultClassLoader()
```
Get the default the ClassLoader to use.

Returns:

the ClassLoader (only null if even the system ClassLoader isn't accessible)

See Also:

Thread.getContextClassLoader(), Class.getClassLoader(), ClassLoader.getSystemClassLoader(), ReflectionUtils.getCallerClass()

getClassLoader
```
@Nullable
public static java.lang.ClassLoader getClassLoader(@Nullable
                                                   java.lang.Class<?> loadedClass)
```
Get the ClassLoader from the loaded class if present.

Parameters:

loadedClass - the optional class was loaded by some ClassLoader

Returns:

the ClassLoader (only null if even the system ClassLoader isn't accessible)

See Also:

getDefaultClassLoader()

getCallerClassLoader
```
@Nullable
public static java.lang.ClassLoader getCallerClassLoader()
```
Return the ClassLoader from the caller class

Returns:

the ClassLoader (only null if the caller class was absent

See Also:

ReflectionUtils.getCallerClass()

findLoadedClasses

public static java.util.Set<java.lang.Class<?>> findLoadedClasses(@Nullable
                                                                  java.lang.ClassLoader classLoader,
                                                                  java.lang.String... classNames)

Find Loaded Class under specified inheritable ClassLoader and class names

Parameters:: classLoader - ClassLoader; classNames - class names
Returns:: Class if loaded, or null

findLoadedClasses

public static java.util.Set<java.lang.Class<?>> findLoadedClasses(@Nullable
                                                                  java.lang.ClassLoader classLoader,
                                                                  java.lang.Iterable<java.lang.String> classNames)

Find Loaded Class under specified inheritable ClassLoader and class names

Parameters:: classLoader - ClassLoader; classNames - class names set
Returns:: Class if loaded, or null

isLoadedClass

public static boolean isLoadedClass(@Nullable
                                    java.lang.ClassLoader classLoader,
                                    java.lang.Class<?> type)

Check specified Class is loaded on specified inheritable ClassLoader

Parameters:: classLoader - ClassLoader; type - Class
Returns:: If Loaded , return true , or false

isLoadedClass

public static boolean isLoadedClass(@Nullable
                                    java.lang.ClassLoader classLoader,
                                    java.lang.String className)

Check specified class name is loaded on specified inheritable ClassLoader

Parameters:: classLoader - ClassLoader; className - class name
Returns:: If Loaded , return true , or false

findLoadedClass

public static java.lang.Class<?> findLoadedClass(@Nullable
                                                 java.lang.ClassLoader classLoader,
                                                 java.lang.String className)

Find Loaded Class under specified inheritable ClassLoader

Parameters:: classLoader - ClassLoader; className - class name
Returns:: Class if loaded , or null

loadClass

@Nullable
public static java.lang.Class<?> loadClass(@Nullable
                                           java.lang.ClassLoader classLoader,
                                           @Nullable
                                           java.lang.String className)

Loaded specified class name under ClassLoader

Parameters:: classLoader - ClassLoader; className - the name of Class
Returns:: Class if can be loaded

loadClass

public static java.lang.Class<?> loadClass(@Nullable
                                           java.lang.ClassLoader classLoader,
                                           @Nullable
                                           java.lang.String className,
                                           boolean cached)

Loaded specified class name under ClassLoader

Parameters:: classLoader - ClassLoader; className - the name of Class; cached - the resolved class is required to be cached or not
Returns:: Class if can be loaded

doLoadClass

protected static java.lang.Class<?> doLoadClass(java.lang.ClassLoader classLoader,
                                                java.lang.String className)

getResources

public static java.util.Set<java.net.URL> getResources(@Nullable
                                                       java.lang.ClassLoader classLoader,
                                                       ClassLoaderUtils.ResourceType resourceType,
                                                       java.lang.String resourceName)
                                                throws java.lang.NullPointerException,
                                                       java.io.IOException

Get the resource URLs Set under specified resource name and type

Parameters:

classLoader - ClassLoader

resourceType - ClassLoaderUtils.ResourceType Enum

resourceName - resource name ，e.g :

Resource Name :"/com/abc/def.log"
Class Name : "java.lang.String"

Returns:

the resource URL under specified resource name and type

Throws:

java.lang.NullPointerException - If any argument is null

java.io.IOException

getResources

public static java.util.Set<java.net.URL> getResources(@Nullable
                                                       java.lang.ClassLoader classLoader,
                                                       java.lang.String resourceName)
                                                throws java.lang.NullPointerException,
                                                       java.io.IOException

Get the resource URLs list under specified resource name

Parameters:

classLoader - ClassLoader

resourceName - resource name ，e.g :

Resource Name :"/com/abc/def.log"
Class Name : "java.lang.String"

Returns:

the resource URL under specified resource name and type

Throws:

java.lang.NullPointerException - If any argument is null

java.io.IOException

getResource
```
public static java.net.URL getResource(java.lang.String resourceName)
                                throws java.lang.NullPointerException
```
Get the resource URL under specified resource name
Parameters:
resourceName - resource name ，e.g :
- Resource Name :"/com/abc/def.log"
- Class Name : "java.lang.String"
Returns:

the resource URL under specified resource name and type

Throws:

java.lang.NullPointerException - If any argument is null

getResource
```
public static java.net.URL getResource(@Nullable
                                       java.lang.ClassLoader classLoader,
                                       java.lang.String resourceName)
                                throws java.lang.NullPointerException
```
Get the resource URL under specified resource name
Parameters:

classLoader - ClassLoader
resourceName - resource name ，e.g :
- Resource Name :"/com/abc/def.log"
- Class Name : "java.lang.String"
Returns:

the resource URL under specified resource name and type

Throws:

java.lang.NullPointerException - If any argument is null

getResource

public static java.net.URL getResource(@Nullable
                                       java.lang.ClassLoader classLoader,
                                       ClassLoaderUtils.ResourceType resourceType,
                                       java.lang.String resourceName)
                                throws java.lang.NullPointerException

Get the resource URL under specified resource name and type

Parameters:

classLoader - ClassLoader

resourceType - ClassLoaderUtils.ResourceType Enum

resourceName - resource name ，e.g :

Resource Name :"/com/abc/def.log"
Class Name : "java.lang.String"

Returns:

the resource URL under specified resource name and type

Throws:

java.lang.NullPointerException - If any argument is null

getResourceAsString
```
public static java.lang.String getResourceAsString(java.lang.String resourceName)
                                            throws java.lang.NullPointerException,
                                                   java.io.IOException
```
Get the content of the specified resource as a String.

Parameters:

resourceName - the name of the resource to load

Returns:

the content of the resource as a String

Throws:

java.lang.NullPointerException - if the resourceName is null

java.io.IOException - if an I/O error occurs while reading the resource

getResourceAsString

public static java.lang.String getResourceAsString(@Nullable
                                                   java.lang.ClassLoader classLoader,
                                                   java.lang.String resourceName)
                                            throws java.lang.NullPointerException,
                                                   java.io.IOException

Get the content of the specified resource as a String.

Parameters:: classLoader - the ClassLoader to use for loading the resource, may be null; resourceName - the name of the resource to load
Returns:: the content of the resource as a String
Throws:: java.lang.NullPointerException - if the resourceName is null; java.io.IOException - if an I/O error occurs while reading the resource

getClassResource

public static java.net.URL getClassResource(@Nullable
                                            java.lang.ClassLoader classLoader,
                                            java.lang.String className)

Get the Class resource URL under specified Class name

Parameters:: classLoader - ClassLoader; className - class name
Returns:: the resource URL under specified resource name and type
Throws:: java.lang.NullPointerException - If any argument is null

getClassResource
```
public static java.net.URL getClassResource(java.lang.Class<?> type)
```
Get the Class resource URL under specified Class

Parameters:

type - type

Returns:

the resource URL under specified resource name and type

Throws:

java.lang.NullPointerException - If any argument is null

getClassResource

public static java.net.URL getClassResource(@Nullable
                                            java.lang.ClassLoader classLoader,
                                            java.lang.Class<?> type)

Get the Class resource URL under specified Class

Parameters:: classLoader - ClassLoader; type - type
Returns:: the resource URL under specified resource name and type
Throws:: java.lang.NullPointerException - If any argument is null

getInheritableClassLoaders

@Nonnull
public static java.util.Set<java.lang.ClassLoader> getInheritableClassLoaders(@Nullable
                                                                              java.lang.ClassLoader classLoader)
                                                                       throws java.lang.NullPointerException

Get all Inheritable ClassLoaders Set (including ClassLoader argument)

Parameters:: classLoader - ClassLoader
Returns:: Read-only Set
Throws:: java.lang.NullPointerException - If classLoader argument is null

getAllLoadedClassesMap

@Nonnull
public static java.util.Map<java.lang.ClassLoader,java.util.Set<java.lang.Class<?>>> getAllLoadedClassesMap(@Nullable
                                                                                                                  java.lang.ClassLoader classLoader)
                                                                                                           throws java.lang.UnsupportedOperationException

Get all loaded classes Map under specified inheritable ClassLoader , ClassLoader as key , its loaded classes Set as value.

Parameters:: classLoader - ClassLoader
Returns:: Read-only Map
Throws:: java.lang.UnsupportedOperationException; java.lang.NullPointerException - If classLoader argument is null

getAllLoadedClasses

@Nonnull
public static java.util.Set<java.lang.Class<?>> getAllLoadedClasses(@Nullable
                                                                    java.lang.ClassLoader classLoader)
                                                             throws java.lang.UnsupportedOperationException

Get all loaded classes Set under specified inheritable ClassLoader

Parameters:: classLoader - ClassLoader
Returns:: Read-only Set
Throws:: java.lang.UnsupportedOperationException - If JVM does not support; java.lang.NullPointerException - If classLoader argument is null

getLoadedClasses

@Nonnull
public static java.util.Set<java.lang.Class<?>> getLoadedClasses(@Nullable
                                                                 java.lang.ClassLoader classLoader)
                                                          throws java.lang.UnsupportedOperationException

Get loaded classes Set under specified ClassLoader( not all inheritable ClassLoaders)

Parameters:: classLoader - ClassLoader
Returns:: Read-only Set
Throws:: java.lang.UnsupportedOperationException - If JVM does not support; java.lang.NullPointerException - If classLoader argument is null
See Also:: getAllLoadedClasses(ClassLoader)

findLoadedClassesInClassPath

public static java.util.Set<java.lang.Class<?>> findLoadedClassesInClassPath(@Nullable
                                                                             java.lang.ClassLoader classLoader)
                                                                      throws java.lang.UnsupportedOperationException

Find loaded classes Set in class path

Parameters:: classLoader - ClassLoader
Returns:: Read-only Set
Throws:: java.lang.UnsupportedOperationException - If JVM does not support

findLoadedClassesInClassPaths

public static java.util.Set<java.lang.Class<?>> findLoadedClassesInClassPaths(@Nullable
                                                                              java.lang.ClassLoader classLoader,
                                                                              java.util.Set<java.lang.String> classPaths)
                                                                       throws java.lang.UnsupportedOperationException

Find loaded classes Set in class paths Set

Parameters:: classLoader - ClassLoader; classPaths - the class paths for the Set of JarFile or classes directory
Returns:: Read-only Set
Throws:: java.lang.UnsupportedOperationException - If JVM does not support
See Also:: findLoadedClass(ClassLoader, String)

findLoadedClassesInClassPath

public static java.util.Set<java.lang.Class<?>> findLoadedClassesInClassPath(@Nullable
                                                                             java.lang.ClassLoader classLoader,
                                                                             java.lang.String classPath)
                                                                      throws java.lang.UnsupportedOperationException

Find loaded classes Set in class path

Parameters:: classLoader - ClassLoader; classPath - the class path for one JarFile or classes directory
Returns:: Read-only Set
Throws:: java.lang.UnsupportedOperationException - If JVM does not support
See Also:: findLoadedClass(ClassLoader, String)

isPresent
```
public static boolean isPresent(@Nullable
                                java.lang.String className)
```
Test the specified class name is present in the default ClassLoader

Parameters:

className - the name of Class

Returns:

If found, return true

isPresent

public static boolean isPresent(@Nullable
                                java.lang.String className,
                                @Nullable
                                java.lang.ClassLoader classLoader)

Test the specified class name is present in the ClassLoader

Parameters:: className - the name of Class; classLoader - ClassLoader
Returns:: If found, return true

resolveClass

public static java.lang.Class<?> resolveClass(@Nullable
                                              java.lang.String className)

Resolve the Class by the specified name in the default ClassLoader

Parameters:: className - the name of Class
Returns:: If can't be resolved , return null

resolveClass

public static java.lang.Class<?> resolveClass(@Nullable
                                              java.lang.String className,
                                              @Nullable
                                              java.lang.ClassLoader classLoader)

Resolve the Class by the specified name and ClassLoader

Parameters:: className - the name of Class; classLoader - ClassLoader
Returns:: If can't be resolved , return null

resolveClass

public static java.lang.Class<?> resolveClass(@Nullable
                                              java.lang.String className,
                                              @Nullable
                                              java.lang.ClassLoader classLoader,
                                              boolean cached)

Resolve the Class by the specified name and ClassLoader

Parameters:: className - the name of Class; classLoader - ClassLoader; cached - the resolved class is required to be cached or not
Returns:: If can't be resolved , return null

findAllClassPathURLs

public static java.util.Set<java.net.URL> findAllClassPathURLs(@Nullable
                                                               java.lang.ClassLoader classLoader)

removeClassPathURL

public static boolean removeClassPathURL(@Nullable
                                         java.lang.ClassLoader classLoader,
                                         java.net.URL url)