1. 将浏覽器位址欄編碼過的中文轉換回中文
/**
* @param fromStr : 要轉換的原始字元串
* @return : 得到轉換後的字元串
*/
private String is(String fromStr) {
StringBuffer stringBufferResult = new StringBuffer();
for (int i = ; i < fromStr.length(); i++) {
char chr = fromStr.charAt(i);
if (chr == '%') {
StringBuffer stringTmp = new StringBuffer();
stringTmp.append(fromStr.charAt(i + )).append(fromStr.charAt(i + ));
//轉換字元，16進制轉換成整型
stringBufferResult.append((char) (Integer.valueOf(stringTmp.toString(), ).intValue()));
i = i + ;
continue;
}
stringBufferResult.append(chr);
}
String newStr = null; //編碼轉換
try {
newStr = new String(stringBufferResult.toString().getBytes("Cp1252"), "UTF-8");
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
}
return newStr;
}
2. 将字元串編碼成 Unicode 形式的字元串與其反轉換
/**
* 将字元串編碼成 Unicode 形式的字元串. 如 "黃" to "\u9EC4"
* Converts unicodes to encoded \\uxxxx and escapes
* special characters with a preceding slash
*
* @param theString 待轉換成Unicode編碼的字元串。
* @param escapeSpace 是否忽略空格，為true時在空格後面是否加個反斜杠。
* @return 傳回轉換後Unicode編碼的字元串。
*/
public static String toEncodedUnicode(String theString, boolean escapeSpace) {
int len = theString.length();
int bufLen = len * ;
if (bufLen < ) {
bufLen = Integer.MAX_VALUE;
}
StringBuffer outBuffer = new StringBuffer(bufLen);
for (int x = ; x < len; x++) {
char aChar = theString.charAt(x);
// Handle common case first, selecting largest block that
// avoids the specials below
if ((aChar > ) && (aChar < )) {
if (aChar == '\\') {
outBuffer.append('\\');
outBuffer.append('\\');
continue;
}
outBuffer.append(aChar);
continue;
}
switch (aChar) {
case ' ':
if (x == || escapeSpace) outBuffer.append('\\');
outBuffer.append(' ');
break;
case '\t':
outBuffer.append('\\');
outBuffer.append('t');
break;
case '\n':
outBuffer.append('\\');
outBuffer.append('n');
break;
case '\r':
outBuffer.append('\\');
outBuffer.append('r');
break;
case '\f':
outBuffer.append('\\');
outBuffer.append('f');
break;
case '=': // Fall through
case ':': // Fall through
case '#': // Fall through
case '!':
outBuffer.append('\\');
outBuffer.append(aChar);
break;
default:
if ((aChar < ) || (aChar > )) {
// 每個unicode有16位，每四位對應的16進制從高位儲存到低位
outBuffer.append('\\');
outBuffer.append('u');
outBuffer.append(toHex((aChar >> ) & ));
outBuffer.append(toHex((aChar >> ) & ));
outBuffer.append(toHex((aChar >> ) & ));
outBuffer.append(toHex(aChar & ));
} else {
outBuffer.append(aChar);
}
}
}
return outBuffer.toString();
}
/**
* 從 Unicode 形式的字元串轉換成對應的編碼的特殊字元串。 如 "\u9EC4" to "黃".
* Converts encoded \\uxxxx to unicode chars
* and changes special saved chars to their original forms
*
* @param in Unicode編碼的字元數組。
* @param off 轉換的起始偏移量。
* @param len 轉換的字元長度。
* @param in 轉換的緩存字元數組。
* @return 完成轉換，傳回編碼前的特殊字元串。
*/
public static String fromEncodedUnicode(char[] in, int off, int len) {
char aChar;
char[] out = new char[len]; // 隻短不長
int outLen = ;
int end = off + len;
while (off < end) {
aChar = in[off++];
if (aChar == '\\') {
aChar = in[off++];
if (aChar == 'u') {
// Read the xxxx
int value = ;
for (int i = ; i < ; i++) {
aChar = in[off++];
switch (aChar) {
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
value = (value << ) + aChar - '0';
break;
case 'a':
case 'b':
case 'c':
case 'd':
case 'e':
case 'f':
value = (value << ) + + aChar - 'a';
break;
case 'A':
case 'B':
case 'C':
case 'D':
case 'E':
case 'F':
value = (value << ) + + aChar - 'A';
break;
default:
throw new IllegalArgumentException("Malformed \\uxxxx encoding.");
}
}
out[outLen++] = (char) value;
} else {
if (aChar == 't') {
aChar = '\t';
} else if (aChar == 'r') {
aChar = '\r';
} else if (aChar == 'n') {
aChar = '\n';
} else if (aChar == 'f') {
aChar = '\f';
}
out[outLen++] = aChar;
}
} else {
out[outLen++] = (char) aChar;
}
}
return new String(out, , outLen);
}
private static final char[] hexDigit = {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A',
'B', 'C', 'D', 'E', 'F'};
private static char toHex(int nibble) {
return hexDigit[(nibble & )];
}
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