java.lang.Class.getDeclaredConstructor()方法实例

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publicConstructor<T> getDeclaredConstructor(Class<?>... parameterTypes)throwsNoSuchMethodException,SecurityException

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import java.lang.reflect.*;
public class ClassDemo {
public static void main(String[] args) {
try {
ClassDemo cls = new ClassDemo();
Class c = cls.getClass();
// constructor with arguments as Double and Long
Class[] cArg = new Class[2];
cArg[0] = Double.class;
cArg[1] = Long.class;
Constructor ct = c.getDeclaredConstructor(cArg);
System.out.println("Constructor = " + ct.toString());
}
catch(NoSuchMethodException e) {
System.out.println(e.toString());
}
catch(SecurityException e) {
System.out.println(e.toString());
}
}
private ClassDemo() {
System.out.println("no argument constructor");
}
public ClassDemo(Double d, Long l) {
this.d = d;
this.l = l;
}
Double d = new Double(3.9d);
Long l = new Long(7687);
} 

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no argument constructor
Constructor=publicClassDemo(java.lang.Double,java.lang.Long)