Java如何使用构造函数对象创建对象？
下面的示例使用构造函数反射通过调用String(String)和String(StringBuilder)构造函数来创建字符串对象。
package org.nhooo.example.reflect;
import java.lang.reflect.Constructor;
import java.lang.reflect.InvocationTargetException;
public class CreateObjectDemo {
public static void main(String[] args) {
Class clazz = String.class;
try {
Constructor constructor = clazz.getConstructor(new Class[] {String.class});
String object = (String) constructor.newInstance(new Object[] {"Hello World!"});
System.out.println("String = " + object);
constructor = clazz.getConstructor(new Class[] {StringBuilder.class});
object = (String) constructor.newInstance(new Object[] {new StringBuilder("Hello Universe!")});
System.out.println("String = " + object);
} catch (NoSuchMethodException e) {
e.printStackTrace();
} catch (InstantiationException e) {
e.printStackTrace();
} catch (IllegalAccessException e) {
e.printStackTrace();
} catch (InvocationTargetException e) {
e.printStackTrace();
}
}
}