Java.lang.Class.getDeclaringClass() 方法

描述

java.lang.Class.getDeclaringClass() 方法返回表示在其中声明它的类的 Class 对象，如果此 Class 对象表示的类或接口是另一个类的成员。 p>

如果此类或接口不是任何其他类的成员，则此方法返回 null。 如果此 Class 对象表示数组类、原始类型或 void，则此方法返回 null。

声明

以下是 java.lang.Class.getDeclaringClass() 方法的声明。

public Class<?> getDeclaringClass()

参数

NA

返回值

该方法返回该类的声明类。

异常

NA

示例

下面的例子展示了 java.lang.Class.getDeclaringClass() 方法的使用。

package com.tutorialspoint;

import java.lang.reflect.*;

public class ClassDemo {

   public static void main(String[] args) {

      // class object associated with class Long
      Class cls = Long.class;

      Method[] m = cls.getMethods();
      for(int i = 0; i < m.length; i++) {
         
         // returns te declaring class
         Class dec = m[i].getDeclaringClass();
         
         // displays all methods
         System.out.println("Method = " + m[i].toString());
         System.out.println(" Declaring class: " + dec.toString());
      }
   }
} 

让我们编译并运行上面的程序，这将产生下面的结果 −

Method = public static int java.lang.Long.numberOfLeadingZeros(long)
Declaring class: class java.lang.Long
Method = public static int java.lang.Long.numberOfTrailingZeros(long)
Declaring class: class java.lang.Long
Method = public static int java.lang.Long.bitCount(long)
Declaring class: class java.lang.Long
Method = public boolean java.lang.Long.equals(java.lang.Object)
Declaring class: class java.lang.Long
Method = public static java.lang.String java.lang.Long.toString(long,int)
Declaring class: class java.lang.Long
Method = public static java.lang.String java.lang.Long.toString(long)
Declaring class: class java.lang.Long
Method = public java.lang.String java.lang.Long.toString()
Declaring class: class java.lang.Long
Method = public int java.lang.Long.hashCode()
Declaring class: class java.lang.Long
Method = public static long java.lang.Long.reverseBytes(long)
Declaring class: class java.lang.Long
Method = public int java.lang.Long.compareTo(java.lang.Long)
Declaring class: class java.lang.Long
Method = public int java.lang.Long.compareTo(java.lang.Object)
Declaring class: class java.lang.Long
Method = public static java.lang.Long java.lang.Long.getLong(java.lang.String)
Declaring class: class java.lang.Long
Method = public static java.lang.Long java.lang.Long.getLong(java.lang.String,long)
Declaring class: class java.lang.Long
Method = public static java.lang.Long java.lang.Long.getLong(java.lang.String,java.lang.Long)
Declaring class: class java.lang.Long
Method = public byte java.lang.Long.byteValue()
Declaring class: class java.lang.Long
Method = public short java.lang.Long.shortValue()
Declaring class: class java.lang.Long
Method = public int java.lang.Long.intValue()
Declaring class: class java.lang.Long
Method = public long java.lang.Long.longValue()
Declaring class: class java.lang.Long
Method = public float java.lang.Long.floatValue()
Declaring class: class java.lang.Long
Method = public double java.lang.Long.doubleValue()
Declaring class: class java.lang.Long
Method = public static java.lang.Long java.lang.Long.valueOf(java.lang.String,int) throws java.lang.NumberFormatException
Declaring class: class java.lang.Long
Method = public static java.lang.Long java.lang.Long.valueOf(java.lang.String) throws java.lang.NumberFormatException
Declaring class: class java.lang.Long
Method = public static java.lang.Long java.lang.Long.valueOf(long)
Declaring class: class java.lang.Long
Method = public static java.lang.String java.lang.Long.toHexString(long)
Declaring class: class java.lang.Long
Method = public static java.lang.Long java.lang.Long.decode(java.lang.String) throws java.lang.NumberFormatException
Declaring class: class java.lang.Long
Method = public static long java.lang.Long.reverse(long)
Declaring class: class java.lang.Long
Method = public static java.lang.String java.lang.Long.toOctalString(long)
Declaring class: class java.lang.Long
Method = public static java.lang.String java.lang.Long.toBinaryString(long)
Declaring class: class java.lang.Long
Method = public static long java.lang.Long.highestOneBit(long)
Declaring class: class java.lang.Long
Method = public static long java.lang.Long.lowestOneBit(long)
Declaring class: class java.lang.Long
Method = public static long java.lang.Long.rotateLeft(long,int)
Declaring class: class java.lang.Long
Method = public static long java.lang.Long.rotateRight(long,int)
Declaring class: class java.lang.Long
Method = public static int java.lang.Long.signum(long)
Declaring class: class java.lang.Long
Method = public static long java.lang.Long.parseLong(java.lang.String,int) throws java.lang.NumberFormatException
Declaring class: class java.lang.Long
Method = public static long java.lang.Long.parseLong(java.lang.String) throws java.lang.NumberFormatException
Declaring class: class java.lang.Long
Method = public final native void java.lang.Object.wait(long) throws java.lang.InterruptedException
Declaring class: class java.lang.Object
Method = public final void java.lang.Object.wait(long,int) throws java.lang.InterruptedException
Declaring class: class java.lang.Object
Method = public final void java.lang.Object.wait() throws java.lang.InterruptedException
Declaring class: class java.lang.Object
Method = public final native java.lang.Class java.lang.Object.getClass()
Declaring class: class java.lang.Object
Method = public final native void java.lang.Object.notify()
Declaring class: class java.lang.Object
Method = public final native void java.lang.Object.notifyAll()
Declaring class: class java.lang.Object