blocks|key|1489978|text|所有类都隐式扩展了已经实现了toString()的Object。由于您的Record类实现了您的接口，并从Object继承了toString()方法，因此就履行了约定。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1489979|entityMap^0|E|A|P|6|10|6|1H|6|1Q|A|0^^$0|@$1|2|3|4|5|6|7|H|8|@$9|I|A|J|B|C]|$9|K|A|L|B|C]|$9|M|A|N|B|C]|$9|O|A|P|B|C]|$9|Q|A|R|B|C]]|D|@]|E|$]]|$1|F|3|-4|5|6|7|S|8|@]|D|@]|E|$]]]|G|$]]

All classes implicitly extends <code>Object</code>, which already has implemented <code>toString()</code>. And since your <code>Record</code> class implements your interface, and inherits the <code>toString()</code> method from <code>Object</code>, the contract is fulfilled.

blocks|key|427124|text|@Override属性是为了确保编译器的安全。这只是为了确保您确实想要重写一个方法，并且没有错误地这样做|type|unstyled|depth|inlineStyleRanges|entityRanges|data|427125|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

The @Override attribute is for compiler safety. It is just to make sure that you really did mean to override a method and that you haven't done it by mistake

blocks|key|1490139|text|因为Object是Object类中定义的所有其他类和toString方法的基类，所以它已经实现了。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1490140|entityMap^0|2|6|Q|8|0^^$0|@$1|2|3|4|5|6|7|H|8|@$9|I|A|J|B|C]|$9|K|A|L|B|C]]|D|@]|E|$]]|$1|F|3|-4|5|6|7|M|8|@]|D|@]|E|$]]]|G|$]]

Because <code>Object</code> is base class of all other classes and <code>toString</code> method defined in Object class, it is already implemented.

blocks|key|428035|text|接口不会从Object继承，但任何将实现您的接口的类都会继承，因此默认情况下会实现它。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|428036|您可能想知道为什么Eclipse在您的界面模板中提供了默认的重写toString：我认为这是为了提醒您以后要实现一些有意义的toString。|428037|entityMap^0|5|6|0|W|8|1Q|8|0^^$0|@$1|2|3|4|5|6|7|J|8|@$9|K|A|L|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|M|8|@$9|N|A|O|B|C]|$9|P|A|Q|B|C]]|D|@]|E|$]]|$1|H|3|-4|5|6|7|R|8|@]|D|@]|E|$]]]|I|$]]

Interfaces do not inherit from <code>Object</code>, but any class that would be implementing your interface will, so it is implemented by default.

You may be wondering why Eclipse provides you with default overridden <code>toString</code> in your interface template: I think of it as a reminder to implement <code>toString</code> to something meaningful later on.

blocks|key|1490189|text|java中的每个类都扩展了java.lang.Object，如果你没有扩展一个类，那么可以考虑隐式对象。|type|unstyled|depth|inlineStyleRanges|offset|length|style|BOLD|entityRanges|data|1490190|只看你的代码：|1490191|public+interface+IRecord+{
++++@Override
++++public+String+toString();

++++public+void+showName(String+name);
}|code-block|syntax|javascript|1490192|为什么在toString()方法中有一个@Override注解，您一定是从某个地方继承了它，|1490193|JLS中提到的：如果接口没有直接的超接口，则该接口隐式声明一个具有签名s的公共抽象成员方法m，返回类型r，并抛出对应于每个具有签名s的公共实例方法m的抛出子句t，返回类型r，以及在Object中声明的抛出子句t。|1490194|这就是为什么您可以在toString()方法上看到覆盖注释的原因。|1490195|现在，当您实现IRecord类时，您的实现类也扩展了Object类，该类具有toString()方法。因此，不需要在这里实现它。|1490196|entityMap^0|D|G|0|0|0|0|7|1|0|0|0^^$0|@$1|2|3|4|5|6|7|W|8|@$9|X|A|Y|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|Z|8|@]|D|@]|E|$]]|$1|H|3|I|5|J|7|10|8|@]|D|@]|E|$K|L]]|$1|M|3|N|5|6|7|11|8|@]|D|@]|E|$]]|$1|O|3|P|5|6|7|12|8|@$9|13|A|14|B|C]]|D|@]|E|$]]|$1|Q|3|R|5|6|7|15|8|@]|D|@]|E|$]]|$1|S|3|T|5|6|7|16|8|@]|D|@]|E|$]]|$1|U|3|-4|5|6|7|17|8|@]|D|@]|E|$]]]|V|$]]

Each and every class extends java.lang.Object in java, if you are not extending one then implicitly Object is considered.

Look at your code only:

<pre><code>public interface IRecord {
 @Override
 public String toString();

 public void showName(String name);
}
</code></pre>

How come you have an @Override annotation in toString() method, you must be inherting it from somewhere, 

As metioned in JLS:
If an interface has no direct superinterfaces, then the interface implicitly declares a public abstract member method m with signature s, return type r, and throws clause t corresponding to each public instance method m with signature s, return type r, and throws clause t declared in Object.

That's why you could see an override annotation above toString() method.

Now when you implement IRecord class, your implementation class also extends the Object class too, which has the toString() method. Hence, its not required to implement it here.

blocks|key|1569022|text|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1569023|在我们声明了所有这些方法并随后在Object类中实现的地方，有没有其他可用的顶级默认接口？|blockquote|1569024|1569025|1569026|从Java+Language+Specification|offset|length|1569027|1569028|如果接口没有直接的超接口，则接口隐式声明一个具有签名s、返回类型r的公共抽象成员方法m，并抛出与每个公共实例方法m相对应的抛出子句t，该方法具有在对象中声明的签名s、返回类型r和抛出子句t，除非接口显式声明了具有相同签名、相同返回类型和兼容的throws子句的方法。|style|BOLD|1569029|1569030|1569031|换句话说，即使是一个空接口也会隐式地继承Object的所有公共方法。这就是Eclipse+(正确地)添加@Override注释的原因。它很可能永远不会因为从Object中删除任何方法而失败，但它有助于避免输入错误：|CODE|1569032|interface+IRecord+{
+++@Override
+++public+String+toSTring();
}

Error:+"The+method+toSTring()+of+type+IRecord+must+override+or+implement+a+supertype+method"|code-block|syntax|javascript|1569033|请参阅问题第二部分的其他答案。|1569034|entityMap|0|LINK|mutability|MUTABLE|url|http://docs.oracle.com/javase/specs/jls/se7/html/jls-9.html#jls-9.2^0|0|0|0|0|1|R|0|0|0|G|Q|1K|A|2M|13|0|0|0|0|2Z|K|6|1G|9|26|6|0|0|0|F|0^^$0|@$1|2|3|-4|4|5|6|18|7|@]|8|@]|9|$]]|$1|A|3|B|4|C|6|19|7|@]|8|@]|9|$]]|$1|D|3|-4|4|5|6|1A|7|@]|8|@]|9|$]]|$1|E|3|-4|4|5|6|1B|7|@]|8|@]|9|$]]|$1|F|3|G|4|5|6|1C|7|@]|8|@$H|1D|I|1E|1|1F]]|9|$]]|$1|J|3|-4|4|5|6|1G|7|@]|8|@]|9|$]]|$1|K|3|L|4|C|6|1H|7|@$H|1I|I|1J|M|N]|$H|1K|I|1L|M|N]|$H|1M|I|1N|M|N]]|8|@]|9|$]]|$1|O|3|-4|4|5|6|1O|7|@]|8|@]|9|$]]|$1|P|3|-4|4|5|6|1P|7|@]|8|@]|9|$]]|$1|Q|3|R|4|5|6|1Q|7|@$H|1R|I|1S|M|N]|$H|1T|I|1U|M|S]|$H|1V|I|1W|M|S]|$H|1X|I|1Y|M|S]]|8|@]|9|$]]|$1|T|3|U|4|V|6|1Z|7|@]|8|@]|9|$W|X]]|$1|Y|3|Z|4|5|6|20|7|@$H|21|I|22|M|N]]|8|@]|9|$]]|$1|10|3|-4|4|5|6|23|7|@]|8|@]|9|$]]]|11|$12|$4|13|14|15|9|$16|17]]]]

<blockquote>
 Is there any other TOP level default interface is available where we have declared all these methods and later implemented in Object class?
</blockquote>

From the <a href="http://docs.oracle.com/javase/specs/jls/se7/html/jls-9.html#jls-9.2" rel="nofollow">Java Language Specification</a>:

<blockquote>
 If an interface has no direct superinterfaces, then the interface implicitly declares a public abstract member method m with signature s, return type r, and throws clause t corresponding to each public instance method m with signature s, return type r, and throws clause t declared in Object, unless a method with the same signature, same return type, and a compatible throws clause is explicitly declared by the interface.
</blockquote>

In other words, even an empty interface implicitly inherits all the public methods from <code>Object</code>. This is the reason why Eclipse (correctly) adds the <code>@Override</code> annotation. It will most likely never fail due to any of the methods being removed from <code>Object</code>, but it can be helpful to avoid typos:

<pre><code>interface IRecord {
 @Override
 public String toSTring();
}

Error: "The method toSTring() of type IRecord must override or implement a supertype method"
</code></pre>

See the other answers for the second part of the question.

I have an interface like below. 

I got this default code in Eclipse. Confused, Why the "@Override" attribute is coming? 

Is there any other TOP level default interface is available where we have declared all these methods and later implemented in Object class?

<pre><code> public interface IRecord {
 @Override
 public String toString();

 public void showName(String name);
 }
</code></pre>

And its one implementation like below

<pre><code>public class Record implements IRecord{

 @Override
 public void showName(String name) {
 //Doing something
 }
}
</code></pre>

It's getting complied very well as expected but I am little surprised why its not asking me to implement <code>toString()</code> method's implementation?

It's there in Object class but Object class is not implementing my interface.

Implementation of Interface methods is required or not

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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我有一个类似下面的界面。我在Eclipse中得到了这个默认代码。困惑，为什么会出现"@Override“属性？在我们声明了所有这些方法并随后在Object类中实现的情况下，是否有其他可用的顶级默认接口？  public interface IRecord {        @Override        public...

问是否需要实现接口方法
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问是否需要实现接口方法EN