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| 7. 1. 6. 演示使用各种类别信息的方法 |
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/*
* file: ClassInfoDemo.java
* package: oreilly.hcj.reflection
*
* This software is granted under the terms of the Common Public License,
* CPL, which may be found at the following URL:
* http://www-124.ibm.com/developerworks/oss/CPLv1.0.htm
*
* Copyright(c) 2003-2005 by the authors indicated in the @author tags.
* All Rights are Reserved by the various authors.
*
########## DO NOT EDIT ABOVE THIS LINE ########## */
import java.io.Serializable;
import java.util.HashSet;
import java.util.Iterator;
import java.util.Set;
/**
* Demonstrates usage of various class information methods.
*
* @author <a href=mailto:kraythe@arcor.de>Robert Simmons jr. (kraythe)</a>
* @version $Revision: 1.3 $
*/
public class ClassInfoDemo {
/**
* Demonstration Method
*
* @param args Demonstration Method.
*/
public static void main(final String[] args) {
final Set classes = new HashSet();
classes.add(Class.class);
classes.add(Comparable.class);
classes.add(Serializable.class);
classes.add(Integer.class);
classes.add(int.class);
classes.add(Float[].class);
classes.add(String.class);
classes.add(double[].class);
classes.add(boolean.class);
// --
System.out.println("Finding interface Class objects in the set.");
Iterator iter = classes.iterator();
while (iter.hasNext()) {
useIsInterface((Class)iter.next());
}
System.out.println("\nFinding primitive Class objects in the set.");
iter = classes.iterator();
while (iter.hasNext()) {
useIsPrimitive((Class)iter.next());
}
System.out.println("\nFinding array Class objects in the set.");
iter = classes.iterator();
while (iter.hasNext()) {
useIsArray((Class)iter.next());
}
}
/**
* Demonstrates usage of <tt>isArray</tt> from Class.
*
* @param dataType The data type to check.
*
* @throws NullPointerException If the user passes null for dataType.
*/
public static void useIsArray(final Class dataType) {
if (dataType == null) {
throw new NullPointerException();
}
if (dataType.isArray()) {
System.out.print(dataType.getName());
System.out.println("\t ==> " + dataType.getComponentType());
}
}
/**
* Demonstrates usage of <tt>isInterface</tt> from Class.
*
* @param dataType The data type to check.
*
* @throws NullPointerException If the user passes null for dataType.
*/
public static void useIsInterface(final Class dataType) {
if (dataType == null) {
throw new NullPointerException();
}
if (dataType.isInterface()) {
System.out.println(dataType.getName());
}
}
/**
* Demonstrates usage of <tt>isPrimitive</tt> from Class.
*
* @param dataType The data type to check.
*
* @throws NullPointerException If the user passes null for dataType.
*/
public static void useIsPrimitive(final Class dataType) {
if (dataType == null) {
throw new NullPointerException();
}
if (dataType.isPrimitive()) {
System.out.println(dataType.getName());
}
}
}
/* ########## End of File ########## */
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