Java Type Helper : Primitive Data Type « Data Type « Java
Java Type Helper
/*
* The contents of this file are subject to the terms
* of the Common Development and Distribution License
* (the "License"). You may not use this file except
* in compliance with the License.
*
* You can obtain a copy of the license at
* glassfish/bootstrap/legal/CDDLv1.0.txt or
* https://glassfish.dev.java.net/public/CDDLv1.0.html.
* See the License for the specific language governing
* permissions and limitations under the License.
*
* When distributing Covered Code, include this CDDL
* HEADER in each file and include the License file at
* glassfish/bootstrap/legal/CDDLv1.0.txt. If applicable,
* add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your
* own identifying information: Portions Copyright [yyyy]
* [name of copyright owner]
*/
/*
* JavaTypeHelper.java
*
* Created on January 22, 2002, 3:39 PM
*/
import java.util.HashMap;
import java.util.Map;
/**
* This is a helper class which provides some basic java type convenience
* methods: extraction of a package from a fully qualified class name,
* extraction of a short (non-qualified) name from a fully qualified class name,
* and various wrapper and primitive type methods.
* @author Rochelle Raccah
*/
public class JavaTypeHelper {
/**
* Map of primitive to wrapper classes
*/
private final static Map _primitiveToWrappers;
/**
* Map of primitive names to primitive classes
*/
private final static Map _primitiveNamesToPrimitives;
/**
* Map of primitive names to wrapper names
*/
private final static Map _primitiveNamesToWrapperNames;
/**
* Map of wrapper classes to primitive names
*/
private final static Map _wrapperToPrimitiveNames;
static {
_primitiveToWrappers = new HashMap(9);
_primitiveToWrappers.put(Boolean.TYPE, Boolean.class);
_primitiveToWrappers.put(Byte.TYPE, Byte.class);
_primitiveToWrappers.put(Character.TYPE, Character.class);
_primitiveToWrappers.put(Double.TYPE, Double.class);
_primitiveToWrappers.put(Float.TYPE, Float.class);
_primitiveToWrappers.put(Integer.TYPE, Integer.class);
_primitiveToWrappers.put(Long.TYPE, Long.class);
_primitiveToWrappers.put(Short.TYPE, Short.class);
_primitiveToWrappers.put(Void.TYPE, Void.class);
_primitiveNamesToPrimitives = new HashMap(9);
_primitiveNamesToPrimitives.put("boolean", Boolean.TYPE); // NOI18N
_primitiveNamesToPrimitives.put("byte", Byte.TYPE); // NOI18N
_primitiveNamesToPrimitives.put("char", Character.TYPE); // NOI18N
_primitiveNamesToPrimitives.put("double", Double.TYPE); // NOI18N
_primitiveNamesToPrimitives.put("float", Float.TYPE); // NOI18N
_primitiveNamesToPrimitives.put("int", Integer.TYPE); // NOI18N
_primitiveNamesToPrimitives.put("long", Long.TYPE); // NOI18N
_primitiveNamesToPrimitives.put("short", Short.TYPE); // NOI18N
_primitiveNamesToPrimitives.put("void", Void.TYPE); // NOI18N
_primitiveNamesToWrapperNames = new HashMap(9);
_primitiveNamesToWrapperNames.put("boolean", "Boolean"); // NOI18N
_primitiveNamesToWrapperNames.put("byte", "Byte"); // NOI18N
_primitiveNamesToWrapperNames.put("char", "Character"); // NOI18N
_primitiveNamesToWrapperNames.put("double", "Double"); // NOI18N
_primitiveNamesToWrapperNames.put("float", "Float"); // NOI18N
_primitiveNamesToWrapperNames.put("int", "Integer"); // NOI18N
_primitiveNamesToWrapperNames.put("long", "Long"); // NOI18N
_primitiveNamesToWrapperNames.put("short", "Short"); // NOI18N
_primitiveNamesToWrapperNames.put("void", "Void"); // NOI18N
_wrapperToPrimitiveNames = new HashMap(9);
_wrapperToPrimitiveNames.put(Boolean.class, "boolean"); // NOI18N
_wrapperToPrimitiveNames.put(Byte.class, "byte"); // NOI18N
_wrapperToPrimitiveNames.put(Character.class, "char"); // NOI18N
_wrapperToPrimitiveNames.put(Double.class, "double"); // NOI18N
_wrapperToPrimitiveNames.put(Float.class, "float"); // NOI18N
_wrapperToPrimitiveNames.put(Integer.class, "int"); // NOI18N
_wrapperToPrimitiveNames.put(Long.class, "long"); // NOI18N
_wrapperToPrimitiveNames.put(Short.class, "short"); // NOI18N
_wrapperToPrimitiveNames.put(Void.class, "void"); // NOI18N
}
/**
* Returns the package portion of the specified class
* @param className the name of the class from which to extract the package
* @return package portion of the specified class
*/
public static String getPackageName(final String className) {
if (className != null) {
final int index = className.lastIndexOf('.');
return ((index != -1) ? className.substring(0, index) : ""); // NOI18N
}
return null;
}
/**
* Returns the name of a class without the package name. For example: if
* input = "java.lang.Object" , then output = "Object".
* @param fully qualified classname
*/
public static String getShortClassName(final String className) {
if (className != null) {
final int index = className.lastIndexOf('.');
return className.substring(index + 1);
}
return null;
}
// primitive/wrapper class utilities
/**
* Returns the wrapper class associated with the supplied primitive class.
* @param primitive the primitive class to be used for lookup.
* @return the associated wrapper class.
*/
public static Class getWrapperClass(Class primitive) {
return (Class) _primitiveToWrappers.get(primitive);
}
/**
* Returns the primitive class associated with the supplied primitive type
* name.
* @param primitiveName the name of the primitive to be used for lookup.
* @return the associated primitive class.
*/
public static Class getPrimitiveClass(String primitiveName) {
return (Class) _primitiveNamesToPrimitives.get(primitiveName);
}
/**
* Returns the name of the wrapper class associated with the supplied
* primitive type name.
* @param primitiveName the name of the primitive to be used for lookup.
* @return the associated wrapper class name.
*/
public static String getWrapperName(String primitiveName) {
return (String) _primitiveNamesToWrapperNames.get(primitiveName);
}
/**
* Returns the name of the primitive type associated with the supplied
* wrapper class.
* @param wrapper the wrapper class to be used for lookup.
* @return the associated primitive type name.
*/
public static String getPrimitiveName(Class wrapper) {
return (String) _wrapperToPrimitiveNames.get(wrapper);
}
/**
* Returns the Boolean wrapper object for true or false corresponding to the
* supplied argument. This is to provide a convenience method for this
* conversion but to prevent calling the Boolean constructor which has been
* determined to be unnecessary and a performance problem. JDK 1.4 provides
* such a method, but some of our code still works with JDK 1.3.
* @param flag the primitive boolean object to be translated to a Boolean
* wrapper.
* @return the associated true/false shared wrapper object
*/
public static Boolean valueOf(boolean flag) {
return (flag ? Boolean.TRUE : Boolean.FALSE);
}
}
