Class ClassUtils
- java.lang.Object
-
- org.apache.commons.lang3.ClassUtils
-
public class ClassUtils extends Object
Operates on classes without using reflection.
This class handles invalid
null
inputs as best it can. Each method documents its behavior in more detail.The notion of a
canonical name
includes the human readable name for the type, for exampleint[]
. The non-canonical method variants work with the JVM names, such as[I
.- Since:
- 2.0
-
-
Nested Class Summary
Nested Classes Modifier and Type Class Description static class
ClassUtils.Interfaces
Inclusivity literals forhierarchy(Class, Interfaces)
.
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Field Summary
Fields Modifier and Type Field Description static String
INNER_CLASS_SEPARATOR
The inner class separator String:"$"
.static char
INNER_CLASS_SEPARATOR_CHAR
The inner class separator character:'$' == {@value}
.static String
PACKAGE_SEPARATOR
The package separator String:"."
.static char
PACKAGE_SEPARATOR_CHAR
The package separator character:'.' == {@value}
.
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Constructor Summary
Constructors Constructor Description ClassUtils()
ClassUtils instances should NOT be constructed in standard programming.
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Method Summary
All Methods Static Methods Concrete Methods Modifier and Type Method Description static List<String>
convertClassesToClassNames(List<Class<?>> classes)
Given aList
ofClass
objects, this method converts them into class names.static List<Class<?>>
convertClassNamesToClasses(List<String> classNames)
Given aList
of class names, this method converts them into classes.static String
getAbbreviatedName(Class<?> cls, int lengthHint)
Gets the abbreviated name of aClass
.static String
getAbbreviatedName(String className, int lengthHint)
Gets the abbreviated class name from aString
.static List<Class<?>>
getAllInterfaces(Class<?> cls)
Gets aList
of all interfaces implemented by the given class and its superclasses.static List<Class<?>>
getAllSuperclasses(Class<?> cls)
Gets aList
of superclasses for the given class.static String
getCanonicalName(Class<?> cls)
Gets the canonical class name for aClass
.static String
getCanonicalName(Class<?> cls, String valueIfNull)
Gets the canonical name for aClass
.static String
getCanonicalName(Object object)
Gets the canonical name for anObject
.static String
getCanonicalName(Object object, String valueIfNull)
Gets the canonical name for anObject
.static Class<?>
getClass(ClassLoader classLoader, String className)
Returns the (initialized) class represented byclassName
using theclassLoader
.static Class<?>
getClass(ClassLoader classLoader, String className, boolean initialize)
Returns the class represented byclassName
using theclassLoader
.static Class<?>
getClass(String className)
Returns the (initialized) class represented byclassName
using the current thread's context class loader.static Class<?>
getClass(String className, boolean initialize)
Returns the class represented byclassName
using the current thread's context class loader.static String
getName(Class<?> cls)
Null-safe version ofcls.getName()
static String
getName(Class<?> cls, String valueIfNull)
Null-safe version ofcls.getName()
static String
getName(Object object)
Null-safe version ofobject.getClass().getName()
static String
getName(Object object, String valueIfNull)
Null-safe version ofobject.getClass().getSimpleName()
static String
getPackageCanonicalName(Class<?> cls)
Gets the package name from the canonical name of aClass
.static String
getPackageCanonicalName(Object object, String valueIfNull)
Gets the package name from the class name of anObject
.static String
getPackageCanonicalName(String name)
Gets the package name from the class name.static String
getPackageName(Class<?> cls)
Gets the package name of aClass
.static String
getPackageName(Object object, String valueIfNull)
Gets the package name of anObject
.static String
getPackageName(String className)
Gets the package name from aString
.static Method
getPublicMethod(Class<?> cls, String methodName, Class<?>... parameterTypes)
Returns the desired Method much likeClass.getMethod
, however it ensures that the returned Method is from a public class or interface and not from an anonymous inner class.static String
getShortCanonicalName(Class<?> cls)
Gets the canonical name minus the package name from aClass
.static String
getShortCanonicalName(Object object, String valueIfNull)
Gets the canonical name minus the package name for anObject
.static String
getShortCanonicalName(String canonicalName)
Gets the canonical name minus the package name from a String.static String
getShortClassName(Class<?> cls)
Gets the class name minus the package name from aClass
.static String
getShortClassName(Object object, String valueIfNull)
Gets the class name of theobject
without the package name or names.static String
getShortClassName(String className)
Gets the class name minus the package name from a String.static String
getSimpleName(Class<?> cls)
Null-safe version ofcls.getSimpleName()
static String
getSimpleName(Class<?> cls, String valueIfNull)
Null-safe version ofcls.getSimpleName()
static String
getSimpleName(Object object)
Null-safe version ofobject.getClass().getSimpleName()
static String
getSimpleName(Object object, String valueIfNull)
Null-safe version ofobject.getClass().getSimpleName()
static Iterable<Class<?>>
hierarchy(Class<?> type)
Gets anIterable
that can iterate over a class hierarchy in ascending (subclass to superclass) order, excluding interfaces.static Iterable<Class<?>>
hierarchy(Class<?> type, ClassUtils.Interfaces interfacesBehavior)
Gets anIterable
that can iterate over a class hierarchy in ascending (subclass to superclass) order.static boolean
isAssignable(Class<?>[] classArray, Class<?>... toClassArray)
Checks if an array of Classes can be assigned to another array of Classes.static boolean
isAssignable(Class<?>[] classArray, Class<?>[] toClassArray, boolean autoboxing)
Checks if an array of Classes can be assigned to another array of Classes.static boolean
isAssignable(Class<?> cls, Class<?> toClass)
Checks if oneClass
can be assigned to a variable of anotherClass
.static boolean
isAssignable(Class<?> cls, Class<?> toClass, boolean autoboxing)
Checks if oneClass
can be assigned to a variable of anotherClass
.static boolean
isInnerClass(Class<?> cls)
Is the specified class an inner class or static nested class.static boolean
isPrimitiveOrWrapper(Class<?> type)
static boolean
isPrimitiveWrapper(Class<?> type)
static Class<?>[]
primitivesToWrappers(Class<?>... classes)
Converts the specified array of primitive Class objects to an array of its corresponding wrapper Class objects.static Class<?>
primitiveToWrapper(Class<?> cls)
Converts the specified primitive Class object to its corresponding wrapper Class object.static Class<?>[]
toClass(Object... array)
Converts an array ofObject
in to an array ofClass
objects.static Class<?>[]
wrappersToPrimitives(Class<?>... classes)
Converts the specified array of wrapper Class objects to an array of its corresponding primitive Class objects.static Class<?>
wrapperToPrimitive(Class<?> cls)
Converts the specified wrapper class to its corresponding primitive class.
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-
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Field Detail
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PACKAGE_SEPARATOR_CHAR
public static final char PACKAGE_SEPARATOR_CHAR
The package separator character:'.' == {@value}
.- See Also:
- Constant Field Values
-
PACKAGE_SEPARATOR
public static final String PACKAGE_SEPARATOR
The package separator String:"."
.
-
INNER_CLASS_SEPARATOR_CHAR
public static final char INNER_CLASS_SEPARATOR_CHAR
The inner class separator character:'$' == {@value}
.- See Also:
- Constant Field Values
-
INNER_CLASS_SEPARATOR
public static final String INNER_CLASS_SEPARATOR
The inner class separator String:"$"
.
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Method Detail
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getShortClassName
public static String getShortClassName(Object object, String valueIfNull)
Gets the class name of the
object
without the package name or names.The method looks up the class of the object and then converts the name of the class invoking
getShortClassName(Class)
(see relevant notes there).- Parameters:
object
- the class to get the short name for, may benull
valueIfNull
- the value to return if the object isnull
- Returns:
- the class name of the object without the package name, or
valueIfNull
if the argumentobject
isnull
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getShortClassName
public static String getShortClassName(Class<?> cls)
Gets the class name minus the package name from a
Class
.This method simply gets the name using
Class.getName()
and then callsgetShortClassName(Class)
. See relevant notes there.- Parameters:
cls
- the class to get the short name for.- Returns:
- the class name without the package name or an empty string. If the class
is an inner class then the returned value will contain the outer class
or classes separated with
.
(dot) character.
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getShortClassName
public static String getShortClassName(String className)
Gets the class name minus the package name from a String.
The string passed in is assumed to be a class name - it is not checked. The string has to be formatted the way as the JDK method
Class.getName()
returns it, and not the usual way as we write it, for example in import statements, or as it is formatted byClass.getCanonicalName()
.The difference is is significant only in case of classes that are inner classes of some other classes. In this case the separator between the outer and inner class (possibly on multiple hierarchy level) has to be
$
(dollar sign) and not.
(dot), as it is returned byClass.getName()
Note that this method is called from the
getShortClassName(Class)
method using the string returned byClass.getName()
.Note that this method differs from
getSimpleName(Class)
in that this will return, for example"Map.Entry"
whilst thejava.lang.Class
variant will simply return"Entry"
. In this example the argumentclassName
is the stringjava.util.Map$Entry
(note the$
sign.- Parameters:
className
- the className to get the short name for. It has to be formatted as returned byClass.getName()
and notClass.getCanonicalName()
- Returns:
- the class name of the class without the package name or an empty string. If the class is
an inner class then value contains the outer class or classes and the separator is replaced
to be
.
(dot) character.
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getSimpleName
public static String getSimpleName(Class<?> cls)
Null-safe version of
cls.getSimpleName()
- Parameters:
cls
- the class for which to get the simple name; may be null- Returns:
- the simple class name or the empty string in case the argument is
null
- Since:
- 3.0
- See Also:
Class.getSimpleName()
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getSimpleName
public static String getSimpleName(Class<?> cls, String valueIfNull)
Null-safe version of
cls.getSimpleName()
- Parameters:
cls
- the class for which to get the simple name; may be nullvalueIfNull
- the value to return if null- Returns:
- the simple class name or
valueIfNull
if the argumentcls
isnull
- Since:
- 3.0
- See Also:
Class.getSimpleName()
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getSimpleName
public static String getSimpleName(Object object)
Null-safe version of
object.getClass().getSimpleName()
It is to note that this method is overloaded and in case the argument
object
is aClass
object then thegetSimpleName(Class)
will be invoked. If this is a significant possibility then the caller should check this case and callgetSimpleName(Class.class)
or just simply use the string literal"Class"
, which is the result of the method in that case.- Parameters:
object
- the object for which to get the simple class name; may be null- Returns:
- the simple class name or the empty string in case the argument is
null
- Since:
- 3.7
- See Also:
Class.getSimpleName()
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getSimpleName
public static String getSimpleName(Object object, String valueIfNull)
Null-safe version of
object.getClass().getSimpleName()
- Parameters:
object
- the object for which to get the simple class name; may be nullvalueIfNull
- the value to return ifobject
isnull
- Returns:
- the simple class name or
valueIfNull
if the argumentobject
isnull
- Since:
- 3.0
- See Also:
Class.getSimpleName()
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getName
public static String getName(Class<?> cls)
Null-safe version of
cls.getName()
- Parameters:
cls
- the class for which to get the class name; may be null- Returns:
- the class name or the empty string in case the argument is
null
- Since:
- 3.7
- See Also:
Class.getSimpleName()
-
getName
public static String getName(Class<?> cls, String valueIfNull)
Null-safe version of
cls.getName()
- Parameters:
cls
- the class for which to get the class name; may be nullvalueIfNull
- the return value if the argumentcls
isnull
- Returns:
- the class name or
valueIfNull
- Since:
- 3.7
- See Also:
Class.getName()
-
getName
public static String getName(Object object)
Null-safe version of
object.getClass().getName()
- Parameters:
object
- the object for which to get the class name; may be null- Returns:
- the class name or the empty String
- Since:
- 3.7
- See Also:
Class.getSimpleName()
-
getName
public static String getName(Object object, String valueIfNull)
Null-safe version of
object.getClass().getSimpleName()
- Parameters:
object
- the object for which to get the class name; may be nullvalueIfNull
- the value to return ifobject
isnull
- Returns:
- the class name or
valueIfNull
- Since:
- 3.0
- See Also:
Class.getName()
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getPackageName
public static String getPackageName(Object object, String valueIfNull)
Gets the package name of an
Object
.- Parameters:
object
- the class to get the package name for, may be nullvalueIfNull
- the value to return if null- Returns:
- the package name of the object, or the null value
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getPackageName
public static String getPackageName(Class<?> cls)
Gets the package name of a
Class
.- Parameters:
cls
- the class to get the package name for, may benull
.- Returns:
- the package name or an empty string
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getPackageName
public static String getPackageName(String className)
Gets the package name from a
String
.The string passed in is assumed to be a class name - it is not checked.
If the class is unpackaged, return an empty string.
- Parameters:
className
- the className to get the package name for, may benull
- Returns:
- the package name or an empty string
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getAbbreviatedName
public static String getAbbreviatedName(Class<?> cls, int lengthHint)
Gets the abbreviated name of a
Class
.- Parameters:
cls
- the class to get the abbreviated name for, may benull
lengthHint
- the desired length of the abbreviated name- Returns:
- the abbreviated name or an empty string
- Throws:
IllegalArgumentException
- if len <= 0- Since:
- 3.4
- See Also:
getAbbreviatedName(String, int)
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getAbbreviatedName
public static String getAbbreviatedName(String className, int lengthHint)
Gets the abbreviated class name from a
String
.The string passed in is assumed to be a class name - it is not checked.
The abbreviation algorithm will shorten the class name, usually without significant loss of meaning.
The abbreviated class name will always include the complete package hierarchy. If enough space is available, rightmost sub-packages will be displayed in full length. The abbreviated package names will be shortened to a single character.
Only package names are shortened, the class simple name remains untouched. (See examples.)
The result will be longer than the desired length only if all the package names shortened to a single character plus the class simple name with the separating dots together are longer than the desired length. In other words, when the class name cannot be shortened to the desired length.
If the class name can be shortened then the final length will be at most
lengthHint
characters.If the
lengthHint
is zero or negative then the method throws exception. If you want to achieve the shortest possible version then use1
as alengthHint
.Examples className len return null 1 "" "java.lang.String" 5 "j.l.String" "java.lang.String" 15 "j.lang.String" "java.lang.String" 30 "java.lang.String" "org.apache.commons.lang3.ClassUtils" 18 "o.a.c.l.ClassUtils" - Parameters:
className
- the className to get the abbreviated name for, may benull
lengthHint
- the desired length of the abbreviated name- Returns:
- the abbreviated name or an empty string if the specified
class name is
null
or empty string. The abbreviated name may be longer than the desired length if it cannot be abbreviated to the desired length. - Throws:
IllegalArgumentException
- iflen <= 0
- Since:
- 3.4
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getAllSuperclasses
public static List<Class<?>> getAllSuperclasses(Class<?> cls)
Gets a
List
of superclasses for the given class.- Parameters:
cls
- the class to look up, may benull
- Returns:
- the
List
of superclasses in order going up from this onenull
if null input
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getAllInterfaces
public static List<Class<?>> getAllInterfaces(Class<?> cls)
Gets a
List
of all interfaces implemented by the given class and its superclasses.The order is determined by looking through each interface in turn as declared in the source file and following its hierarchy up. Then each superclass is considered in the same way. Later duplicates are ignored, so the order is maintained.
- Parameters:
cls
- the class to look up, may benull
- Returns:
- the
List
of interfaces in order,null
if null input
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convertClassNamesToClasses
public static List<Class<?>> convertClassNamesToClasses(List<String> classNames)
Given a
List
of class names, this method converts them into classes.A new
List
is returned. If the class name cannot be found,null
is stored in theList
. If the class name in theList
isnull
,null
is stored in the outputList
.- Parameters:
classNames
- the classNames to change- Returns:
- a
List
of Class objects corresponding to the class names,null
if null input - Throws:
ClassCastException
- if classNames contains a non String entry
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convertClassesToClassNames
public static List<String> convertClassesToClassNames(List<Class<?>> classes)
Given a
List
ofClass
objects, this method converts them into class names.A new
List
is returned.null
objects will be copied into the returned list asnull
.- Parameters:
classes
- the classes to change- Returns:
- a
List
of class names corresponding to the Class objects,null
if null input - Throws:
ClassCastException
- ifclasses
contains a non-Class
entry
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isAssignable
public static boolean isAssignable(Class<?>[] classArray, Class<?>... toClassArray)
Checks if an array of Classes can be assigned to another array of Classes.
This method calls
isAssignable
for each Class pair in the input arrays. It can be used to check if a set of arguments (the first parameter) are suitably compatible with a set of method parameter types (the second parameter).Unlike the
Class.isAssignableFrom(java.lang.Class)
method, this method takes into account widenings of primitive classes andnull
s.Primitive widenings allow an int to be assigned to a
long
,float
ordouble
. This method returns the correct result for these cases.Null
may be assigned to any reference type. This method will returntrue
ifnull
is passed in and the toClass is non-primitive.Specifically, this method tests whether the type represented by the specified
Class
parameter can be converted to the type represented by thisClass
object via an identity conversion widening primitive or widening reference conversion. See The Java Language Specification, sections 5.1.1, 5.1.2 and 5.1.4 for details.Since Lang 3.0, this method will default behavior for calculating assignability between primitive and wrapper types corresponding to the running Java version; i.e. autoboxing will be the default behavior in VMs running Java versions > 1.5.
- Parameters:
classArray
- the array of Classes to check, may benull
toClassArray
- the array of Classes to try to assign into, may benull
- Returns:
true
if assignment possible
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isAssignable
public static boolean isAssignable(Class<?>[] classArray, Class<?>[] toClassArray, boolean autoboxing)
Checks if an array of Classes can be assigned to another array of Classes.
This method calls
isAssignable
for each Class pair in the input arrays. It can be used to check if a set of arguments (the first parameter) are suitably compatible with a set of method parameter types (the second parameter).Unlike the
Class.isAssignableFrom(java.lang.Class)
method, this method takes into account widenings of primitive classes andnull
s.Primitive widenings allow an int to be assigned to a
long
,float
ordouble
. This method returns the correct result for these cases.Null
may be assigned to any reference type. This method will returntrue
ifnull
is passed in and the toClass is non-primitive.Specifically, this method tests whether the type represented by the specified
Class
parameter can be converted to the type represented by thisClass
object via an identity conversion widening primitive or widening reference conversion. See The Java Language Specification, sections 5.1.1, 5.1.2 and 5.1.4 for details.- Parameters:
classArray
- the array of Classes to check, may benull
toClassArray
- the array of Classes to try to assign into, may benull
autoboxing
- whether to use implicit autoboxing/unboxing between primitives and wrappers- Returns:
true
if assignment possible
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isPrimitiveOrWrapper
public static boolean isPrimitiveOrWrapper(Class<?> type)
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isPrimitiveWrapper
public static boolean isPrimitiveWrapper(Class<?> type)
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isAssignable
public static boolean isAssignable(Class<?> cls, Class<?> toClass)
Checks if one
Class
can be assigned to a variable of anotherClass
.Unlike the
Class.isAssignableFrom(java.lang.Class)
method, this method takes into account widenings of primitive classes andnull
s.Primitive widenings allow an int to be assigned to a long, float or double. This method returns the correct result for these cases.
Null
may be assigned to any reference type. This method will returntrue
ifnull
is passed in and the toClass is non-primitive.Specifically, this method tests whether the type represented by the specified
Class
parameter can be converted to the type represented by thisClass
object via an identity conversion widening primitive or widening reference conversion. See The Java Language Specification, sections 5.1.1, 5.1.2 and 5.1.4 for details.Since Lang 3.0, this method will default behavior for calculating assignability between primitive and wrapper types corresponding to the running Java version; i.e. autoboxing will be the default behavior in VMs running Java versions > 1.5.
- Parameters:
cls
- the Class to check, may be nulltoClass
- the Class to try to assign into, returns false if null- Returns:
true
if assignment possible
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isAssignable
public static boolean isAssignable(Class<?> cls, Class<?> toClass, boolean autoboxing)
Checks if one
Class
can be assigned to a variable of anotherClass
.Unlike the
Class.isAssignableFrom(java.lang.Class)
method, this method takes into account widenings of primitive classes andnull
s.Primitive widenings allow an int to be assigned to a long, float or double. This method returns the correct result for these cases.
Null
may be assigned to any reference type. This method will returntrue
ifnull
is passed in and the toClass is non-primitive.Specifically, this method tests whether the type represented by the specified
Class
parameter can be converted to the type represented by thisClass
object via an identity conversion widening primitive or widening reference conversion. See The Java Language Specification, sections 5.1.1, 5.1.2 and 5.1.4 for details.- Parameters:
cls
- the Class to check, may be nulltoClass
- the Class to try to assign into, returns false if nullautoboxing
- whether to use implicit autoboxing/unboxing between primitives and wrappers- Returns:
true
if assignment possible
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primitiveToWrapper
public static Class<?> primitiveToWrapper(Class<?> cls)
Converts the specified primitive Class object to its corresponding wrapper Class object.
NOTE: From v2.2, this method handles
Void.TYPE
, returningVoid.TYPE
.- Parameters:
cls
- the class to convert, may be null- Returns:
- the wrapper class for
cls
orcls
ifcls
is not a primitive.null
if null input. - Since:
- 2.1
-
primitivesToWrappers
public static Class<?>[] primitivesToWrappers(Class<?>... classes)
Converts the specified array of primitive Class objects to an array of its corresponding wrapper Class objects.
- Parameters:
classes
- the class array to convert, may be null or empty- Returns:
- an array which contains for each given class, the wrapper class or
the original class if class is not a primitive.
null
if null input. Empty array if an empty array passed in. - Since:
- 2.1
-
wrapperToPrimitive
public static Class<?> wrapperToPrimitive(Class<?> cls)
Converts the specified wrapper class to its corresponding primitive class.
This method is the counter part of
primitiveToWrapper()
. If the passed in class is a wrapper class for a primitive type, this primitive type will be returned (e.g.Integer.TYPE
forInteger.class
). For other classes, or if the parameter is null, the return value is null.- Parameters:
cls
- the class to convert, may be null- Returns:
- the corresponding primitive type if
cls
is a wrapper class, null otherwise - Since:
- 2.4
- See Also:
primitiveToWrapper(Class)
-
wrappersToPrimitives
public static Class<?>[] wrappersToPrimitives(Class<?>... classes)
Converts the specified array of wrapper Class objects to an array of its corresponding primitive Class objects.
This method invokes
wrapperToPrimitive()
for each element of the passed in array.- Parameters:
classes
- the class array to convert, may be null or empty- Returns:
- an array which contains for each given class, the primitive class or
null if the original class is not a wrapper class.
null
if null input. Empty array if an empty array passed in. - Since:
- 2.4
- See Also:
wrapperToPrimitive(Class)
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isInnerClass
public static boolean isInnerClass(Class<?> cls)
Is the specified class an inner class or static nested class.
- Parameters:
cls
- the class to check, may be null- Returns:
true
if the class is an inner or static nested class, false if not ornull
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getClass
public static Class<?> getClass(ClassLoader classLoader, String className, boolean initialize) throws ClassNotFoundException
Returns the class represented byclassName
using theclassLoader
. This implementation supports the syntaxes "java.util.Map.Entry[]
", "java.util.Map$Entry[]
", "[Ljava.util.Map.Entry;
", and "[Ljava.util.Map$Entry;
".- Parameters:
classLoader
- the class loader to use to load the classclassName
- the class nameinitialize
- whether the class must be initialized- Returns:
- the class represented by
className
using theclassLoader
- Throws:
ClassNotFoundException
- if the class is not found
-
getClass
public static Class<?> getClass(ClassLoader classLoader, String className) throws ClassNotFoundException
Returns the (initialized) class represented byclassName
using theclassLoader
. This implementation supports the syntaxes "java.util.Map.Entry[]
", "java.util.Map$Entry[]
", "[Ljava.util.Map.Entry;
", and "[Ljava.util.Map$Entry;
".- Parameters:
classLoader
- the class loader to use to load the classclassName
- the class name- Returns:
- the class represented by
className
using theclassLoader
- Throws:
ClassNotFoundException
- if the class is not found
-
getClass
public static Class<?> getClass(String className) throws ClassNotFoundException
Returns the (initialized) class represented byclassName
using the current thread's context class loader. This implementation supports the syntaxes "java.util.Map.Entry[]
", "java.util.Map$Entry[]
", "[Ljava.util.Map.Entry;
", and "[Ljava.util.Map$Entry;
".- Parameters:
className
- the class name- Returns:
- the class represented by
className
using the current thread's context class loader - Throws:
ClassNotFoundException
- if the class is not found
-
getClass
public static Class<?> getClass(String className, boolean initialize) throws ClassNotFoundException
Returns the class represented byclassName
using the current thread's context class loader. This implementation supports the syntaxes "java.util.Map.Entry[]
", "java.util.Map$Entry[]
", "[Ljava.util.Map.Entry;
", and "[Ljava.util.Map$Entry;
".- Parameters:
className
- the class nameinitialize
- whether the class must be initialized- Returns:
- the class represented by
className
using the current thread's context class loader - Throws:
ClassNotFoundException
- if the class is not found
-
getPublicMethod
public static Method getPublicMethod(Class<?> cls, String methodName, Class<?>... parameterTypes) throws NoSuchMethodException
Returns the desired Method much like
Class.getMethod
, however it ensures that the returned Method is from a public class or interface and not from an anonymous inner class. This means that the Method is invokable and doesn't fall foul of Java bug 4071957).Set set = Collections.unmodifiableSet(...); Method method = ClassUtils.getPublicMethod(set.getClass(), "isEmpty", new Class[0]); Object result = method.invoke(set, new Object[]);
- Parameters:
cls
- the class to check, not nullmethodName
- the name of the methodparameterTypes
- the list of parameters- Returns:
- the method
- Throws:
NullPointerException
- if the class is nullSecurityException
- if a security violation occurredNoSuchMethodException
- if the method is not found in the given class or if the method doesn't conform with the requirements
-
toClass
public static Class<?>[] toClass(Object... array)
Converts an array of
Object
in to an array ofClass
objects. If any of these objects is null, a null element will be inserted into the array.This method returns
null
for anull
input array.- Parameters:
array
- anObject
array- Returns:
- a
Class
array,null
if null array input - Since:
- 2.4
-
getShortCanonicalName
public static String getShortCanonicalName(Object object, String valueIfNull)
Gets the canonical name minus the package name for an
Object
.- Parameters:
object
- the class to get the short name for, may be nullvalueIfNull
- the value to return if null- Returns:
- the canonical name of the object without the package name, or the null value
- Since:
- 2.4
-
getCanonicalName
public static String getCanonicalName(Class<?> cls)
Gets the canonical class name for a
Class
.- Parameters:
cls
- the class for which to get the canonical class name; may be null- Returns:
- the canonical name of the class, or the empty String
- Since:
- 3.7
- See Also:
Class.getCanonicalName()
-
getCanonicalName
public static String getCanonicalName(Class<?> cls, String valueIfNull)
Gets the canonical name for a
Class
.- Parameters:
cls
- the class for which to get the canonical class name; may be nullvalueIfNull
- the return value if null- Returns:
- the canonical name of the class, or
valueIfNull
- Since:
- 3.7
- See Also:
Class.getCanonicalName()
-
getCanonicalName
public static String getCanonicalName(Object object)
Gets the canonical name for an
Object
.- Parameters:
object
- the object for which to get the canonical class name; may be null- Returns:
- the canonical name of the object, or the empty String
- Since:
- 3.7
- See Also:
Class.getCanonicalName()
-
getCanonicalName
public static String getCanonicalName(Object object, String valueIfNull)
Gets the canonical name for an
Object
.- Parameters:
object
- the object for which to get the canonical class name; may be nullvalueIfNull
- the return value if null- Returns:
- the canonical name of the object or
valueIfNull
- Since:
- 3.7
- See Also:
Class.getCanonicalName()
-
getShortCanonicalName
public static String getShortCanonicalName(Class<?> cls)
Gets the canonical name minus the package name from a
Class
.- Parameters:
cls
- the class for which to get the short canonical class name; may be null- Returns:
- the canonical name without the package name or an empty string
- Since:
- 2.4
-
getShortCanonicalName
public static String getShortCanonicalName(String canonicalName)
Gets the canonical name minus the package name from a String.
The string passed in is assumed to be a class name - it is not checked.
Note that this method is mainly designed to handle the arrays and primitives properly. If the class is an inner class then the result value will not contain the outer classes. This way the behavior of this method is different from
getShortClassName(String)
. The argument in that case is class name and not canonical name and the return value retains the outer classes.Note that there is no way to reliably identify the part of the string representing the package hierarchy and the part that is the outer class or classes in case of an inner class. Trying to find the class would require reflective call and the class itself may not even be on the class path. Relying on the fact that class names start with capital letter and packages with lower case is heuristic.
It is recommended to use
getShortClassName(String)
for cases when the class is an inner class and use this method for cases it is designed for.Examples return value input ""
(String)null
"Map.Entry"
java.util.Map.Entry.class.getName()
"Entry"
java.util.Map.Entry.class.getCanonicalName()
"ClassUtils"
"org.apache.commons.lang3.ClassUtils"
"ClassUtils[]"
"[Lorg.apache.commons.lang3.ClassUtils;"
"ClassUtils[][]"
"[[Lorg.apache.commons.lang3.ClassUtils;"
"ClassUtils[]"
"org.apache.commons.lang3.ClassUtils[]"
"ClassUtils[][]"
"org.apache.commons.lang3.ClassUtils[][]"
"int[]"
"[I"
"int[]"
int[].class.getCanonicalName()
"int[]"
int[].class.getName()
"int[][]"
"[[I"
"int[]"
"int[]"
"int[][]"
"int[][]"
- Parameters:
canonicalName
- the class name to get the short name for- Returns:
- the canonical name of the class without the package name or an empty string
- Since:
- 2.4
-
getPackageCanonicalName
public static String getPackageCanonicalName(Object object, String valueIfNull)
Gets the package name from the class name of an
Object
.- Parameters:
object
- the class to get the package name for, may be nullvalueIfNull
- the value to return if null- Returns:
- the package name of the object, or the null value
- Since:
- 2.4
-
getPackageCanonicalName
public static String getPackageCanonicalName(Class<?> cls)
Gets the package name from the canonical name of a
Class
.- Parameters:
cls
- the class to get the package name for, may benull
.- Returns:
- the package name or an empty string
- Since:
- 2.4
-
getPackageCanonicalName
public static String getPackageCanonicalName(String name)
Gets the package name from the class name.
The string passed in is assumed to be a class name - it is not checked.
If the class is in the default package, return an empty string.
- Parameters:
name
- the name to get the package name for, may benull
- Returns:
- the package name or an empty string
- Since:
- 2.4
-
hierarchy
public static Iterable<Class<?>> hierarchy(Class<?> type)
Gets anIterable
that can iterate over a class hierarchy in ascending (subclass to superclass) order, excluding interfaces.- Parameters:
type
- the type to get the class hierarchy from- Returns:
- Iterable an Iterable over the class hierarchy of the given class
- Since:
- 3.2
-
hierarchy
public static Iterable<Class<?>> hierarchy(Class<?> type, ClassUtils.Interfaces interfacesBehavior)
Gets anIterable
that can iterate over a class hierarchy in ascending (subclass to superclass) order.- Parameters:
type
- the type to get the class hierarchy frominterfacesBehavior
- switch indicating whether to include or exclude interfaces- Returns:
- Iterable an Iterable over the class hierarchy of the given class
- Since:
- 3.2
-
-