Java Hashtable rehash（）方法与示例

- 日理万妓 2023-03-05 15:53 21阅读 0赞

## 哈希表类rehash()方法 **(**Hashtable Class rehash() method**)** ##

*  **rehash() method** is available in java.util package.
    
    **rehash()方法**在java.util包中可用。
 *  **rehash() method** is used to extend the capacity and it is invoked implicitly if the number of keys limit exceeds hashtable capacity.
    
    **rehash()方法**用于扩展容量，如果键数限制超过哈希表容量，则会隐式调用该方法。
 *  **rehash() 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.
    
    **rehash()方法**是一种非静态方法，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。
 *  **rehash() method** does not throw an exception at the time of extending capacity.
    
    **rehash()方法**在扩展容量时不会引发异常。

**Syntax:**

**句法：**

public void rehash();

**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 void, it returns nothing.

该方法的返回类型为void ，不返回任何内容。

**Example:**

**例：**

// Java program to demonstrate the example 
    // of void rehash() method of Hashtable 
    
    import java.util.*;
    
    public class RehashOfHashtable extends Hashtable {
        
        public static void main(String[] args) {
        
            //Instantiate a hashtable object  
            RehashOfHashtable ht = new RehashOfHashtable();
    
            // By using put() method is to
            // add the linked values in an
            // Hashtable ht
            ht.put(10, "C");
            ht.put(20, "C++");
            ht.put(30, "JAVA");
            ht.put(40, "PHP");
            ht.put(50, "SFDC");
    
            // Display Hashtable
            System.out.println("Hashtable: " + ht);
    
            // By using rehash() method is to increase
            // the capacity and re-organizes internally
            // this Hashtable
    
            ht.rehash();
            System.out.println("ht.size(): " + ht.size());
        }
    }

**Output**

**输出量**

Hashtable: {10=C, 20=C++, 30=JAVA, 40=PHP, 50=SFDC}
    ht.size(): 5

> 翻译自: [https://www.includehelp.com/java/hashtable-rehash-method-with-example.aspx][https_www.includehelp.com_java_hashtable-rehash-method-with-example.aspx]

[https_www.includehelp.com_java_hashtable-rehash-method-with-example.aspx]: https://www.includehelp.com/java/hashtable-rehash-method-with-example.aspx