哈希表

来源：互联网发布：centos修改ip地址编辑：程序博客网时间：2024/06/04 00:47

以员工为例：

package d15哈希表;//员工信息类public class Info {    private String key;    private String name;    public Info(String key ,String name){        this.key=key;        this.name=name;    }    public String getKey() {        return key;    }    public void setKey(String key) {        this.key = key;    }    public String getName() {        return name;    }    public void setName(String name) {        this.name = name;    }}

package d15哈希表;import java.math.BigInteger;public class HashTable {    private Info [] arr;    //默认构造方法    public HashTable(){        arr= new Info[100];    }    //指定数组初始化大小    public HashTable(int maxSize){        arr = new Info[maxSize];    }    //插入数据    public void insert( Info info){        arr[hashCode(info.getKey())]= info;    }    private int hashCode(String key) {        BigInteger hashVal = new BigInteger("0");        BigInteger pow27 = new BigInteger("1");        for(int i = key.length()-1;i>=0;i--){            int letter = key.charAt(i)-96;            BigInteger letterB = new BigInteger(String.valueOf(letter));            hashVal=hashVal.add(letterB.multiply(pow27));            pow27 = pow27.multiply(new BigInteger(String.valueOf(27)));        }        return hashVal.mod(new BigInteger(String.valueOf(arr.length))).intValue();    }    //查找数据    public Info find (String key ){        return arr[hashCode(key)];    }}

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