freemarker.template.utility

Class ClassUtil

java.lang.Object

freemarker.template.utility.ClassUtil

public class ClassUtil
extends java.lang.Object

Method Summary

Modifier and Type	Method and Description
static java.lang.Class	boxingClassToPrimitiveClass(java.lang.Class boxingClass) The exact reverse of primitiveClassToBoxingClass(java.lang.Class).
static java.lang.Class	forName(java.lang.String className) Similar to Class.forName(java.lang.String), but attempts to load through the thread context class loader.
static java.lang.Class<?>	getArrayClass(java.lang.Class<?> elementType, int dimensions) Returns the array type that corresponds to the element type and the given number of array dimensions.
static java.lang.String	getFTLTypeDescription(TemplateModel tm) Returns the type description of a value with FTL terms (not plain class name), as it should be used in type-related error messages and for debugging purposes.
static java.io.InputStream	getReasourceAsStream(java.lang.Class<?> baseClass, java.lang.String resource, boolean optional) Very similar to Class.getResourceAsStream(String), but throws IOException instead of returning null if optional is false, and attempts to work around "IllegalStateException: zip file closed" and similar sun.net.www.protocol.jar.JarURLConnection-related glitches.
static java.io.InputStream	getReasourceAsStream(java.lang.ClassLoader classLoader, java.lang.String resource, boolean optional) Same as getReasourceAsStream(Class, String, boolean), but uses a ClassLoader directly instead of a Class.
static java.lang.String	getShortClassName(java.lang.Class pClass) Same as getShortClassName(pClass, false).
static java.lang.String	getShortClassName(java.lang.Class pClass, boolean shortenFreeMarkerClasses) Returns a class name without "java.lang." and "java.util." prefix, also shows array types in a format like int[]; useful for printing class names in error messages.
static java.lang.String	getShortClassNameOfObject(java.lang.Object obj) Same as getShortClassNameOfObject(pClass, false).
static java.lang.String	getShortClassNameOfObject(java.lang.Object obj, boolean shortenFreeMarkerClasses) getShortClassName(Class, boolean) called with object.getClass(), but returns the fictional class name Null for a null value.
static boolean	isNumerical(java.lang.Class type) Tells if a type is numerical; works both for primitive types and classes.
static java.util.Properties	loadProperties(java.lang.Class<?> baseClass, java.lang.String resource) Loads a class loader resource into a Properties; tries to work around "zip file closed" and related sun.net.www.protocol.jar.JarURLConnection glitches.
static java.lang.Class	primitiveClassToBoxingClass(java.lang.Class primitiveClass) Gets the wrapper class for a primitive class, like Integer for int, also returns Void for void.
static java.lang.Class<?>	resolveIfPrimitiveTypeName(java.lang.String typeName) Returns the Class for a primitive type name, or null if it's not the name of a primitive type.

Methods inherited from class java.lang.Object

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

Method Detail

forName

public static java.lang.Class forName(java.lang.String className)
                               throws java.lang.ClassNotFoundException

Similar to Class.forName(java.lang.String), but attempts to load through the thread context class loader. Only if thread context class loader is inaccessible, or it can't find the class will it attempt to fall back to the class loader that loads the FreeMarker classes.

Throws:

java.lang.ClassNotFoundException

resolveIfPrimitiveTypeName

public static java.lang.Class<?> resolveIfPrimitiveTypeName(java.lang.String typeName)

Returns the Class for a primitive type name, or null if it's not the name of a primitive type.

Since:

2.3.30

getArrayClass

public static java.lang.Class<?> getArrayClass(java.lang.Class<?> elementType,
                                               int dimensions)

Returns the array type that corresponds to the element type and the given number of array dimensions. If the dimension is 0, it just returns the element type as is.

Since:

2.3.30

getShortClassName

public static java.lang.String getShortClassName(java.lang.Class pClass)

Same as getShortClassName(pClass, false).

Since:

2.3.20

getShortClassName

public static java.lang.String getShortClassName(java.lang.Class pClass,
                                                 boolean shortenFreeMarkerClasses)

Returns a class name without "java.lang." and "java.util." prefix, also shows array types in a format like int[]; useful for printing class names in error messages.

Parameters:

pClass - can be null, in which case the method returns null.

shortenFreeMarkerClasses - if true, it will also shorten FreeMarker class names. The exact rules aren't specified and might change over time, but right now, freemarker.ext.beans.NumberModel for example becomes to f.e.b.NumberModel.

Since:

2.3.20

getShortClassNameOfObject

public static java.lang.String getShortClassNameOfObject(java.lang.Object obj)

Same as getShortClassNameOfObject(pClass, false).

Since:

2.3.20

getShortClassNameOfObject

public static java.lang.String getShortClassNameOfObject(java.lang.Object obj,
                                                         boolean shortenFreeMarkerClasses)

getShortClassName(Class, boolean) called with object.getClass(), but returns the fictional class name Null for a null value.

Since:

2.3.20

getFTLTypeDescription

public static java.lang.String getFTLTypeDescription(TemplateModel tm)

Returns the type description of a value with FTL terms (not plain class name), as it should be used in type-related error messages and for debugging purposes. The exact format is not specified and might change over time, but currently it's something like "string (wrapper: f.t.SimpleScalar)" or "sequence+hash+string (ArrayList wrapped into f.e.b.CollectionModel)".

Since:

2.3.20

primitiveClassToBoxingClass

public static java.lang.Class primitiveClassToBoxingClass(java.lang.Class primitiveClass)

Gets the wrapper class for a primitive class, like Integer for int, also returns Void for void.

Parameters:

primitiveClass - A Class like int.type, boolean.type, etc. If it's not a primitive class, or it's null, then the parameter value is returned as is. Note that performance-wise the method assumes that it's a primitive class.

Since:

2.3.21

boxingClassToPrimitiveClass

public static java.lang.Class boxingClassToPrimitiveClass(java.lang.Class boxingClass)

The exact reverse of primitiveClassToBoxingClass(java.lang.Class).

Since:

2.3.21

isNumerical

public static boolean isNumerical(java.lang.Class type)

Tells if a type is numerical; works both for primitive types and classes.

Parameters:

type - can't be null

Since:

2.3.21

getReasourceAsStream

public static java.io.InputStream getReasourceAsStream(java.lang.Class<?> baseClass,
                                                       java.lang.String resource,
                                                       boolean optional)
                                                throws java.io.IOException

Very similar to Class.getResourceAsStream(String), but throws IOException instead of returning null if optional is false, and attempts to work around "IllegalStateException: zip file closed" and similar sun.net.www.protocol.jar.JarURLConnection-related glitches. These are caused by bugs outside of FreeMarker. Note that in cases where the JAR resource becomes broken concurrently, similar errors can still occur later when the InputStream is read (loadProperties(Class, String) works that around as well).

Returns:

If optional is false, it's never null, otherwise null indicates that the resource doesn't exist.

Throws:

java.io.IOException - If the resource wasn't found, or other IOException occurs.

Since:

2.3.27

getReasourceAsStream

public static java.io.InputStream getReasourceAsStream(java.lang.ClassLoader classLoader,
                                                       java.lang.String resource,
                                                       boolean optional)
                                                throws java.io.IOException

Same as getReasourceAsStream(Class, String, boolean), but uses a ClassLoader directly instead of a Class.

Throws:

java.io.IOException

Since:

2.3.27

loadProperties

public static java.util.Properties loadProperties(java.lang.Class<?> baseClass,
                                                  java.lang.String resource)
                                           throws java.io.IOException

Loads a class loader resource into a Properties; tries to work around "zip file closed" and related sun.net.www.protocol.jar.JarURLConnection glitches.

Throws:

java.io.IOException

Since:

2.3.27