Java中汉字、字母、数字占多少字节呢?

占用字节数，在不同的编码格式中，字节数不同
   有时一个汉字占用2个或3个或4个字节

下文笔者将使用示例的方式讲述汉字、字母、数字占用字节数

 
public void test1() throws UnsupportedEncodingException {
	String a = "毛";
	System.out.println("UTF-8编码长度:"+a.getBytes("UTF-8").length);
	System.out.println("GBK编码长度:"+a.getBytes("GBK").length);
	System.out.println("GB2312编码长度:"+a.getBytes("GB2312").length);
	System.out.println("==========================================");

	String c = "0x20001";
	System.out.println("UTF-8编码长度:"+c.getBytes("UTF-8").length);
	System.out.println("GBK编码长度:"+c.getBytes("GBK").length);
	System.out.println("GB2312编码长度:"+c.getBytes("GB2312").length);
	System.out.println("==========================================");

	char[] arr = Character.toChars(0x20001);
	String s = new String(arr);
	System.out.println("char array length:" + arr.length);
	System.out.println("content:|  " + s + " |");
	System.out.println("String length:" + s.length());
	System.out.println("UTF-8编码长度:"+s.getBytes("UTF-8").length);
	System.out.println("GBK编码长度:"+s.getBytes("GBK").length);
	System.out.println("GB2312编码长度:"+s.getBytes("GB2312").length);
	System.out.println("==========================================");
}



-----运行以上代码,将输出以下信息----

UTF-8编码长度:3
GBK编码长度:2
GB2312编码长度:2
==========================================
UTF-8编码长度:7
GBK编码长度:7
GB2312编码长度:7
==========================================
char array length:2
content:|  ? |
String length:2
UTF-8编码长度:4
GBK编码长度:1
GB2312编码长度:1
==========================================