每日学习笔记(23)

1,从前端传过来的参数是"\u9676\u9676\u6D4B\u8BD5\u8D26\u53F701"这样的unicode编码，需要将其转换为中文字符串，发现java.util.Properties类中有一个loadConvert函数可以完成这件事，直接copy过来使用。

public static String loadConvert(char[] in, int off, int len, char[] convtBuf) {
if (convtBuf.length < len) {
int newLen = len * 2;
if (newLen < 0) {
newLen = Integer.MAX_VALUE;
}
convtBuf = new char[newLen];
}
char aChar;
char[] out = convtBuf;
int outLen = 0;
int end = off + len;

while (off < end) {
aChar = in[off++];
if (aChar == '\\') {
aChar = in[off++];
if (aChar == 'u') {
// Read the xxxx
int value = 0;
for (int i = 0; i < 4; 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 << 4) + aChar - '0';
break;
case 'a':
case 'b':
case 'c':
case 'd':
case 'e':
case 'f':
value = (value << 4) + 10 + aChar - 'a';
break;
case 'A':
case 'B':
case 'C':
case 'D':
case 'E':
case 'F':
value = (value << 4) + 10 + 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, 0, outLen);