java URLEncoder 和Base64.encode()

参考:

http://www.360doc.com/content/10/1103/12/1485725_66213001.shtml (URLEncode)

http://blog.csdn.net/uikoo9/article/details/27981219

计算机中的数据都是二进制的，不管是字符串还是文件，而加密后的也是二进制的，

而我们要看到的往往是字符串，本文就介绍了将byte[]转为各种进制以及base64编码。

是一种编码方式，可以理解为复杂的进制，很多算法加密后输出的都是byte[]，而这个byte[]对我们显示的形式是不友好的（乱码），

所以一般都是转为base64的，当然也可以转为其他进制。

   /**
        * 导入commons-codec.jar包
        * @param s
        */
    public static void main(String[] s){

        String sss = "Aa1 23Aa+程序";
        byte[] bytes = null;
        try {
            bytes = sss.getBytes("UTF-8");
            for(byte b: bytes){
                System.out.print(b+"(#)");
            }
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        }

        byte[] encode;
        try {

            encode = org.apache.commons.codec.binary.Base64.encodeBase64(bytes);
            System.out.print("\n");
            for(byte b: encode){
                System.out.print(b+"(y)");
            }
            byte[] bytess  = org.apache.commons.codec.binary.Base64.decodeBase64(encode);
            System.out.print("\n");
            for(byte b: bytess){
                System.out.print(b+"(x)");
            }
            String sss2 = new String(bytess, "UTF-8");
            System.out.print("\nsss2 === "+ sss2);

            sss = "Aa123 Aa程序#程序*程序+and程序";
            String encode1 = java.net.URLEncoder.encode(sss, "UTF-8");
            System.out.println("\njava.net.URLEncoder 结果: " + encode1);
            String sss3 = URLDecoder.decode(encode1, "UTF-8");
            System.out.println("\njava.net.URLDecoder 结果: " + sss3);
        } catch (Exception e) {
            e.printStackTrace();
        }
运行结果:
65(#)97(#)49(#)32(#)50(#)51(#)65(#)97(#)43(#)-25(#)-88(#)-117(#)-27(#)-70(#)-113(#)
81(y)87(y)69(y)120(y)73(y)68(y)73(y)122(y)81(y)87(y)69(y)114(y)53(y)54(y)105(y)76(y)53(y)98(y)113(y)80(y)
65(x)97(x)49(x)32(x)50(x)51(x)65(x)97(x)43(x)-25(x)-88(x)-117(x)-27(x)-70(x)-113(x)
sss2 === Aa1 23Aa+程序
java.net.URLEncoder 结果: Aa123+Aa%E7%A8%8B%E5%BA%8F%23%E7%A8%8B%E5%BA%8F*%E7%A8%8B%E5%BA%8F%2Band%E7%A8%8B%E5%BA%8F

java.net.URLDecoder 结果: Aa123 Aa程序#程序*程序+and程序

===============================自写base64encode方法=======================================

package com.game.charge.sign;

public final class Base64 {

static private final int BASELENGTH = 128;
static private final int LOOKUPLENGTH = 64;
static private final int TWENTYFOURBITGROUP = 24;
static private final int EIGHTBIT = 8;
static private final int SIXTEENBIT = 16;
static private final int FOURBYTE = 4;
static private final int SIGN = -128;
static private final char PAD = '=';
static private final boolean fDebug = false;
static final private byte[] base64Alphabet = new byte[BASELENGTH];
static final private char[] lookUpBase64Alphabet = new char[LOOKUPLENGTH];

static {
for (int i = 0; i < BASELENGTH; ++i) {
base64Alphabet[i] = -1;
}
for (int i = 'Z'; i >= 'A'; i--) {
base64Alphabet[i] = (byte) (i - 'A');
}
for (int i = 'z'; i >= 'a'; i--) {
base64Alphabet[i] = (byte) (i - 'a' + 26);
}

for (int i = '9'; i >= '0'; i--) {
base64Alphabet[i] = (byte) (i - '0' + 52);
}

base64Alphabet['+'] = 62;
base64Alphabet['/'] = 63;

for (int i = 0; i <= 25; i++) {
lookUpBase64Alphabet[i] = (char) ('A' + i);
}

for (int i = 26, j = 0; i <= 51; i++, j++) {
lookUpBase64Alphabet[i] = (char) ('a' + j);
}

for (int i = 52, j = 0; i <= 61; i++, j++) {
lookUpBase64Alphabet[i] = (char) ('0' + j);
}
lookUpBase64Alphabet[62] = (char) '+';
lookUpBase64Alphabet[63] = (char) '/';

}

private static boolean isWhiteSpace(char octect) {
return (octect == 0x20 || octect == 0xd || octect == 0xa || octect == 0x9);
}

private static boolean isPad(char octect) {
return (octect == PAD);
}

private static boolean isData(char octect) {
return (octect < BASELENGTH && base64Alphabet[octect] != -1);
}

/**
* Encodes hex octects into Base64
*
* @param binaryData Array containing binaryData
* @return Encoded Base64 array
*/
public static String encode(byte[] binaryData) {

if (binaryData == null) {
return null;
}

int lengthDataBits = binaryData.length * EIGHTBIT;
if (lengthDataBits == 0) {
return "";
}

int fewerThan24bits = lengthDataBits % TWENTYFOURBITGROUP;
int numberTriplets = lengthDataBits / TWENTYFOURBITGROUP;
int numberQuartet = fewerThan24bits != 0 ? numberTriplets + 1 : numberTriplets;
char encodedData[] = null;

encodedData = new char[numberQuartet * 4];

byte k = 0, l = 0, b1 = 0, b2 = 0, b3 = 0;

int encodedIndex = 0;
int dataIndex = 0;
if (fDebug) {
System.out.println("number of triplets = " + numberTriplets);
}

for (int i = 0; i < numberTriplets; i++) {
b1 = binaryData[dataIndex++];
b2 = binaryData[dataIndex++];
b3 = binaryData[dataIndex++];

if (fDebug) {
System.out.println("b1= " + b1 + ", b2= " + b2 + ", b3= " + b3);
}

l = (byte) (b2 & 0x0f);
k = (byte) (b1 & 0x03);

byte val1 = ((b1 & SIGN) == 0) ? (byte) (b1 >> 2) : (byte) ((b1) >> 2 ^ 0xc0);
byte val2 = ((b2 & SIGN) == 0) ? (byte) (b2 >> 4) : (byte) ((b2) >> 4 ^ 0xf0);
byte val3 = ((b3 & SIGN) == 0) ? (byte) (b3 >> 6) : (byte) ((b3) >> 6 ^ 0xfc);

if (fDebug) {
System.out.println("val2 = " + val2);
System.out.println("k4 = " + (k << 4));
System.out.println("vak = " + (val2 | (k << 4)));
}

encodedData[encodedIndex++] = lookUpBase64Alphabet[val1];
encodedData[encodedIndex++] = lookUpBase64Alphabet[val2 | (k << 4)];
encodedData[encodedIndex++] = lookUpBase64Alphabet[(l << 2) | val3];
encodedData[encodedIndex++] = lookUpBase64Alphabet[b3 & 0x3f];
}

// form integral number of 6-bit groups
if (fewerThan24bits == EIGHTBIT) {
b1 = binaryData[dataIndex];
k = (byte) (b1 & 0x03);
if (fDebug) {
System.out.println("b1=" + b1);
System.out.println("b1<<2 = " + (b1 >> 2));
}
byte val1 = ((b1 & SIGN) == 0) ? (byte) (b1 >> 2) : (byte) ((b1) >> 2 ^ 0xc0);
encodedData[encodedIndex++] = lookUpBase64Alphabet[val1];
encodedData[encodedIndex++] = lookUpBase64Alphabet[k << 4];
encodedData[encodedIndex++] = PAD;
encodedData[encodedIndex++] = PAD;
} else if (fewerThan24bits == SIXTEENBIT) {
b1 = binaryData[dataIndex];
b2 = binaryData[dataIndex + 1];
l = (byte) (b2 & 0x0f);
k = (byte) (b1 & 0x03);

byte val1 = ((b1 & SIGN) == 0) ? (byte) (b1 >> 2) : (byte) ((b1) >> 2 ^ 0xc0);
byte val2 = ((b2 & SIGN) == 0) ? (byte) (b2 >> 4) : (byte) ((b2) >> 4 ^ 0xf0);

encodedData[encodedIndex++] = lookUpBase64Alphabet[val1];
encodedData[encodedIndex++] = lookUpBase64Alphabet[val2 | (k << 4)];
encodedData[encodedIndex++] = lookUpBase64Alphabet[l << 2];
encodedData[encodedIndex++] = PAD;
}

return new String(encodedData);
}

/**
* Decodes Base64 data into octects
*
* @param encoded string containing Base64 data
* @return Array containind decoded data.
*/
public static byte[] decode(String encoded) {

if (encoded == null) {
return null;
}

char[] base64Data = encoded.toCharArray();
// remove white spaces
int len = removeWhiteSpace(base64Data);

if (len % FOURBYTE != 0) {
return null;//should be divisible by four
}

int numberQuadruple = (len / FOURBYTE);

if (numberQuadruple == 0) {
return new byte[0];
}

byte decodedData[] = null;
byte b1 = 0, b2 = 0, b3 = 0, b4 = 0;
char d1 = 0, d2 = 0, d3 = 0, d4 = 0;

int i = 0;
int encodedIndex = 0;
int dataIndex = 0;
decodedData = new byte[(numberQuadruple) * 3];

for (; i < numberQuadruple - 1; i++) {

if (!isData((d1 = base64Data[dataIndex++])) || !isData((d2 = base64Data[dataIndex++]))
|| !isData((d3 = base64Data[dataIndex++]))
|| !isData((d4 = base64Data[dataIndex++]))) {
return null;
}//if found "no data" just return null

b1 = base64Alphabet[d1];
b2 = base64Alphabet[d2];
b3 = base64Alphabet[d3];
b4 = base64Alphabet[d4];

decodedData[encodedIndex++] = (byte) (b1 << 2 | b2 >> 4);
decodedData[encodedIndex++] = (byte) (((b2 & 0xf) << 4) | ((b3 >> 2) & 0xf));
decodedData[encodedIndex++] = (byte) (b3 << 6 | b4);
}

if (!isData((d1 = base64Data[dataIndex++])) || !isData((d2 = base64Data[dataIndex++]))) {
return null;//if found "no data" just return null
}

b1 = base64Alphabet[d1];
b2 = base64Alphabet[d2];

d3 = base64Data[dataIndex++];
d4 = base64Data[dataIndex++];
if (!isData((d3)) || !isData((d4))) {//Check if they are PAD characters
if (isPad(d3) && isPad(d4)) {
if ((b2 & 0xf) != 0)//last 4 bits should be zero
{
return null;
}
byte[] tmp = new byte[i * 3 + 1];
System.arraycopy(decodedData, 0, tmp, 0, i * 3);
tmp[encodedIndex] = (byte) (b1 << 2 | b2 >> 4);
return tmp;
} else if (!isPad(d3) && isPad(d4)) {
b3 = base64Alphabet[d3];
if ((b3 & 0x3) != 0)//last 2 bits should be zero
{
return null;
}
byte[] tmp = new byte[i * 3 + 2];
System.arraycopy(decodedData, 0, tmp, 0, i * 3);
tmp[encodedIndex++] = (byte) (b1 << 2 | b2 >> 4);
tmp[encodedIndex] = (byte) (((b2 & 0xf) << 4) | ((b3 >> 2) & 0xf));
return tmp;
} else {
return null;
}
} else { //No PAD e.g 3cQl
b3 = base64Alphabet[d3];
b4 = base64Alphabet[d4];
decodedData[encodedIndex++] = (byte) (b1 << 2 | b2 >> 4);
decodedData[encodedIndex++] = (byte) (((b2 & 0xf) << 4) | ((b3 >> 2) & 0xf));
decodedData[encodedIndex++] = (byte) (b3 << 6 | b4);

}

return decodedData;
}

/**
* remove WhiteSpace from MIME containing encoded Base64 data.
*
* @param data the byte array of base64 data (with WS)
* @return the new length
*/
private static int removeWhiteSpace(char[] data) {
if (data == null) {
return 0;
}

// count characters that's not whitespace
int newSize = 0;
int len = data.length;
for (int i = 0; i < len; i++) {
if (!isWhiteSpace(data[i])) {
data[newSize++] = data[i];
}
}
return newSize;
}
}

public static void main(String[] s){
String sss = "Aa123Aa程序";
byte[] bytes = null;
try {
bytes = sss.getBytes("UTF-8");
for(byte b: bytes){
System.out.print(b+"(#)");
}
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
}

String encode;
try {

encode = Base64.encode(bytes);
System.out.println("\nBase64.encode 结果: " + encode);
byte[] bytess = Base64.decode(encode);
for(byte b: bytess){
System.out.print(b+"(#)");
}
String sss2 = new String(bytess, "UTF-8");
System.out.print("\nsss2 === "+ sss2);

sss = "Aa123 Aa程序#程序*程序+and程序";
encode = java.net.URLEncoder.encode(sss, "UTF-8");
System.out.println("\njava.net.URLEncoder 结果: " + encode);
String sss3 = URLDecoder.decode(encode, "UTF-8");
System.out.println("\njava.net.URLDecoder 结果: " + sss3);
} catch (Exception e) {
e.printStackTrace();
}

运行结果:

65(#)97(#)49(#)50(#)51(#)65(#)97(#)-25(#)-88(#)-117(#)-27(#)-70(#)-113(#)
Base64.encode 结果: QWExMjNBYeeoi+W6jw==
65(#)97(#)49(#)50(#)51(#)65(#)97(#)-25(#)-88(#)-117(#)-27(#)-70(#)-113(#)
sss2 === Aa123Aa程序
java.net.URLEncoder 结果: Aa123+Aa%E7%A8%8B%E5%BA%8F%23%E7%A8%8B%E5%BA%8F*%E7%A8%8B%E5%BA%8F%2Band%E7%A8%8B%E5%BA%8F

java.net.URLDecoder 结果: Aa123 Aa程序#程序*程序+and程序