java.lang.object的方法使用说明 java.lang.Object中getClass()方法有...
java.lang.object\u7684\u5b9e\u73b0\u65b9\u6cd5\u6709\u54ea\u4e9bJava.lang.object\u7c7b\u4e2d\u6709\u51e0\u4e2a\u65b9\u6cd5\u4e0d\u662ffinal\u7684\uff0c\u6211\u4eec\u4f1a\u7ecf\u5e38\u7528\u91cd\u5199\u5b83\u4eec\uff0c
protected Object clone() \u521b\u5efa\u5e76\u8fd4\u56de\u6b64\u5bf9\u8c61\u7684\u4e00\u4e2a\u526f\u672c\u3002
boolean equals(Object obj) \u6307\u793a\u67d0\u4e2a\u5176\u4ed6\u5bf9\u8c61\u662f\u5426\u4e0e\u6b64\u5bf9\u8c61\u201c\u76f8\u7b49\u201d\u3002
protected void finalize() \u5f53\u5783\u573e\u56de\u6536\u5668\u786e\u5b9a\u4e0d\u5b58\u5728\u5bf9\u8be5\u5bf9\u8c61\u7684\u66f4\u591a\u5f15\u7528\u65f6\uff0c\u7531\u5bf9\u8c61\u7684\u5783\u573e\u56de\u6536\u5668\u8c03\u7528\u6b64\u65b9\u6cd5\u3002
int hashCode() \u8fd4\u56de\u8be5\u5bf9\u8c61\u7684\u54c8\u5e0c\u7801\u503c\u3002
String toString() \u8fd4\u56de\u8be5\u5bf9\u8c61\u7684\u5b57\u7b26\u4e32\u8868\u793a\u3002
1\u3001clone()
\u6211\u4eec\u4e3a\u4ec0\u4e48\u8981\u7528clone()?
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public class Test
{
public static void main(String[] args){
A a1=new A();
A a2=new A();
a1.name="a1";
a2=a1;
a2.name="a2";
System.out.println("a1.name="+a1.name);
System.out.println("a2.name="+a2.name);
}
}
class A
{
public String name;
}
\u8f93\u51fa\u7ed3\u679c\u4e3a\uff1aa1.name=a2;
a2.name=a2;
\u4e0b\u9762\u8fd9\u4e2a\u662f\u91cd\u5199\u4e86clone()\u7684\u4f8b\u5b50
public class Test
{
public static void main(String[] args) throws CloneNotSupportedException {
A a1=new A();
A a2=new A();
a1.name="a1";
a2=(A) a1.clone();
a2.name="a2";
System.out.println("a1.name="+a1.name);
System.out.println("a2.name="+a2.name);
}
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aa\u5e26\u7684\u65b9\u6cd5\u6709\u4ec0\u4e48\u7528.
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Collection c=new ArrayList();
Class class=c.getClass();
List ll=c.getMethod("sublist",int.class,int.class).invoke(c,0,0);
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Collection c\u4ecd\u7136\u80fd\u8c03\u7528sublist()\u65b9\u6cd5
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\u4ed6\u7528\u7684\u8bed\u6cd5\u5c31\u662fgetClass().getMethods();
1、equals()方法：用于测试某个对象是否同另一个对象相等。它在Object类中的实现是判断两个对象是否指向同一块内存区域。这种测试用处不大，因为即使内容相同的对象，内存区域也是不同的。如果想测试对象是否相等，就需要覆盖此方法，进行更有意义的比较。例如
class Employee{
... //此例子来自《java核心技术》卷一
public boolean equals(Object otherObj){
//快速测试是否是同一个对象
if(this == otherObj) return true;
//如果显式参数为null，必须返回false
if(otherObj == null) reutrn false;
//如果类不匹配，就不可能相等
if(getClass() != otherObj.getClass()) return false;
//现在已经知道otherObj是个非空的Employee对象
Employee other = (Employee)otherObj;
//测试所有的字段是否相等
return name.equals(otherName)
&& salary == other.salary
&& hireDay.equals(other.hireDay);
}
}
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绛旓細瀵硅薄:java.lang.Object@922804宸插瓨鍦! 瀵硅薄:java.lang.Object@e29820宸插瓨鍦! 鍒楄〃List鐨勫ぇ灏:9998 閲嶅鍏冪礌鐨勪釜鏁:2 鍒楄〃List鐨勫ぇ灏:10000 閲嶅鍏冪礌鐨勪釜鏁:0 鏌ョ湅Object婧愪唬鐮: public String toString() { return getClass().getName() + "@" + Integer.toHexString(hashCode()); 宸茶禐杩 宸茶俯杩< 浣犲...
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绛旓細java.awt 绫籐istjava.lang.Object java.awt.Component java.awt.List鎵鏈夊凡瀹炵幇鐨勬帴鍙: ImageObserver, ItemSelectable, MenuContainer, Serializable, Accessible ---public class Listextends Componentimplements ItemSelectable, AccessibleList 缁勪欢涓虹敤鎴锋彁渚涗簡涓涓彲婊氬姩鐨勬枃鏈」鍒楄〃銆傚彲璁剧疆姝 list,浣垮叾鍏佽鐢ㄦ埛杩涜...
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