Commons codec jar包詳解

Commons項目中用來處理常用的編碼方法的工具類包，例如DES、SHA1、MD5、Base64, 及 hex, metaphone, soundex 等編碼演算。

JavaDoc:http://www.osctools.net/apidocs/apidoc?api=commons-codec

官網下載地址：http://commons.apache.org/codec/

使用：

A.Base64 編解碼

 

package demo;

import org.apache.commons.codec.binary.Base64;

public class Base64Test {

    public static void main(String[] args) {

        Base64 base64 = new Base64();
        String str = "中文";
        byte[] enbytes = null;
        String encodeStr = null;
        byte[] debytes = null;
        String decodeStr = null;

        enbytes = base64.encode(str.getBytes());
        encodeStr = new String(enbytes);
        debytes = base64.decode(enbytes);
        decodeStr = new String(debytes);
    
        System.out.println("編碼前:" + str);
        System.out.println("編碼后:" + encodeStr);
        System.out.println("解碼后:" + decodeStr);
    }
}

B.Hex 編解碼

 

 

package demo;

import org.apache.commons.codec.DecoderException;
import org.apache.commons.codec.binary.Hex;

public class HexTest {

    public static void main(String[] args) throws DecoderException {

        Hex hex = new Hex();
        String str = "中文";
        char[] enbytes = null;
        String encodeStr = null;
        byte[] debytes = null;
        String decodeStr = null;

        enbytes = hex.encodeHex(str.getBytes());
        encodeStr = new String(enbytes);
        debytes = hex.decodeHex(enbytes);
        decodeStr = new String(debytes);

        System.out.println("編碼前:" + str);
        System.out.println("編碼后:" + encodeStr);
        System.out.println("解碼后:" + decodeStr);
    }
}

C.Metaphone 及 Soundex 編碼

 

package demo;

import org.apache.commons.codec.language.Metaphone;
import org.apache.commons.codec.language.RefinedSoundex;
import org.apache.commons.codec.language.Soundex;

public class LanguageTest {

    public static void main(String[] args) {

        Metaphone metaphone = new Metaphone();
        RefinedSoundex refinedSoundex = new RefinedSoundex();
        Soundex soundex = new Soundex();
        for (int i = 0; i < 2; i++) {
            String str = (i == 0) ? "resume" : "resin";
            String mString = null;
            String rString = null;
            String sString = null;
            try {
                mString = metaphone.encode(str);
                rString = refinedSoundex.encode(str);
                sString = soundex.encode(str);
            } catch (Exception ex) {
                ;
            }
            System.out.println("Original:" + str);
            System.out.println("Metaphone:" + mString);
            System.out.println("RefinedSoundex:" + rString);
            System.out.println("Soundex:" + sString + "\n");
        }
    }
}

Metaphone 建立出相同的key給發音相似的單字, 比 Soundex 還要准確, 但是 Metaphone 沒有固定長度, Soundex 則是固定第一個英文字加上3個數字. 這通常是用在類似音比對, 也可以用在 MP3 的軟件開發.