Java ListResourceBundle getKeys（）方法与示例

ListResourceBundle类的getContents()方法 (ListResourceBundle Class getContents() method)

getContents() method is available in java.util package.
getContents()方法在java.util包中可用。
getContents() method is used to return an enumeration of all the keys that exist in this ListResourceBundle and its superclass.
getContents()方法用于返回此ListResourceBundle及其超类中存在的所有键的枚举。
getContents() method is a non-static method, it is accessible with the class object only and if we try to access the method with the class name then we will get an error.
getContents()方法是一个非静态方法，只能通过类对象访问，如果尝试使用类名称访问该方法，则会收到错误消息。
getContents() method does not throw an exception at the time of returning an enumeration of elements.
在返回元素枚举时， getContents()方法不会引发异常。

Syntax:

句法：

    public Enumeration getKeys();

Parameter(s):

参数：

It does not accept any parameter.
它不接受任何参数。

Return value:

返回值：

The return type of the method is Enumeration, it gets an Enumeration of all the existing keys in this ListResourceBundle and its super bundle.

该方法的返回类型为Enumeration ，它获取此ListResourceBundle及其超级捆绑包中所有现有键的Enumeration。

Example:

例：

// Java program to demonstrate the example 
// of Enumeration getKeys()  method of  
// ListResourceBundle 
import java.util.*;
// Instantiates a class that extends
// ListResourceBundle 
class GetKey extends ListResourceBundle {
// By using getContent() method is to
// get the contents in the form of 
// 2D objects
protected Object[][] getContents() {
return new Object[][] {
{
"10",
"C"
}, {
"20",
"C++"
}, {
"30",
"JAVA"
}, {
"40",
"SFDC"
}, {
"50",
"PHP"
}
};
}
}
public class Main {
public static void main(String[] args) {
// Instantiates an object of
// GetKeys
GetKey get_c = new GetKey();
// By using getKeys() method is 
// return all the keys in the 
// form of an Enumeration
System.out.println("get_c.getKeys(): ");
for (Enumeration en = get_c.getKeys(); en.hasMoreElements();)
System.out.println(en.nextElement());
}
}

Output

输出量