Unicode转中文 UnicodeToZh

这个也是昨晚看Unicode转中文的时候在blogjava看到的，今天想起也放上来吧和另外那篇纯调用java工具的做对比。
网上的方法是用的char数组做转换，而需求呢，我们得到的是一个stringbuffer流，所以就重写一个方法，输入参数是unicode的stringbuffer，输出是中文的stringbuffer。

	/**
	 * 将unicode编码的StringBuffer流转码为中文的StringBuffer流
	 * @param unicode的StringBuffer流
	 * @return中文的StringBuffer流
	 */
	public static StringBuffer fromUnicode(StringBuffer sb) {
		int length=sb.length();
		int index=0;
		char aChar;
		StringBuffer result=new StringBuffer();
		
		while (index<length) {
			aChar = sb.charAt(index++);
			if (aChar == '\\') {
				aChar = sb.charAt(index++);
				if (aChar == 'u') {
					// Read the xxxx
					int value = 0;
					for (int i = 0; i < 4; i++) {
						aChar = sb.charAt(index++);
						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.");
						}
					}
					result.append((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';
					}
					result.append( aChar);
				}
			} else {
				result.append((char) aChar);
			}
		}
		return result;		
	}

网上原文java代码：

public class UnicodeToZh {
	
	public static void main(String[] args) {
		char []c="\u300a\u654f\u6377\u8f6f\u4ef6".toCharArray();
		UnicodeToZh zh=new UnicodeToZh();
		zh.fromUnicode(c, 0, c.length, c);
		System.out.println(c);
	}
	
    public UnicodeToZh() {
    	
    }
    
	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 & 0xF)];
	}

	/**
	 * 将字符串编码成 Unicode 。
	 * @param theString 待转换成Unicode编码的字符串。
	 * @param escapeSpace 是否忽略空格。
	 * @return 返回转换后Unicode编码的字符串。
	 */
	public static String toUnicode(String theString, boolean escapeSpace) {
		int len = theString.length();
		int bufLen = len * 2;
		if (bufLen < 0) {
			bufLen = Integer.MAX_VALUE;
		}
		StringBuffer outBuffer = new StringBuffer(bufLen);

		for (int x = 0; x < len; x++) {
			char aChar = theString.charAt(x);
			// Handle common case first, selecting largest block that
			// avoids the specials below
			if ((aChar > 61) && (aChar < 127)) {
				if (aChar == '\\') {
					outBuffer.append('\\');
					outBuffer.append('\\');
					continue;
				}
				outBuffer.append(aChar);
				continue;
			}
			switch (aChar) {
			case ' ':
				if (x == 0 || 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 < 0x0020) || (aChar > 0x007e)) {
					outBuffer.append('\\');
					outBuffer.append('u');
					outBuffer.append(toHex((aChar >> 12) & 0xF));
					outBuffer.append(toHex((aChar >> 8) & 0xF));
					outBuffer.append(toHex((aChar >> 4) & 0xF));
					outBuffer.append(toHex(aChar & 0xF));
				} else {
					outBuffer.append(aChar);
				}
			}
		}
		return outBuffer.toString();
	}

	/**
	 * 从 Unicode 码转换成编码前的特殊字符串。
	 * @param in  Unicode编码的字符数组。
	 * @param off 转换的起始偏移量。
	 * @param len 转换的字符长度。
	 * @param convtBuf 转换的缓存字符数组。
	 * @return 完成转换，返回编码前的特殊字符串。
	 */
	public static String fromUnicode(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);
	}
}