【Java基础专题】编码与乱码(06)---字符的各种值转换

package example.encoding;

/** *//**
 * The Class ChineseValidator.
 */
public class CharacterValueConveter {

    /** *//**
     * The main method.
     * 
     * @param args the arguments
     */
    public static void main(String args[]) {
        CharacterValueConveter conveter = new CharacterValueConveter();
        conveter.testConvertion("中文");
    }

    /** *//**
     * Test convertion.
     * 
     * @param content the content
     */
    public void testConvertion(String content) {
        byte[] bytes = content.getBytes();
        
        System.out.println("Original String : " + content);
        System.out.println();
        
        // Get bytes array
        System.out.println("Convert string to bytes array : ");
        for (int i = 0; i < bytes.length; i++) {
            System.out.println(" byte[" + i + "]=" + bytes[i]);
        }
        System.out.println();

        // Get each character and unicode
        System.out.println("Start to convert by character: " + "\n");
        for (int j = 0; j < content.length(); j++) {
            char c = content.charAt(j);
            printAllValue(c);
        }
    }

    /** *//**
     * Prints the all value.
     * 
     * @param c the c
     */
    public void printAllValue(char c) {

        byte b = (byte) c;
        int i = (int) c;
        short s = (short) c;
        String binaryString = Integer.toBinaryString(i);
        String hexString = Integer.toHexString(i);

        StringBuffer output = new StringBuffer();
        // Base value
        output.append("Character : ").append(c).append("\n");
        output.append(" byte value : ").append(b).append("\n");
        output.append(" int value : ").append(i).append("\n");
        output.append(" short value : ").append(s).append("\n");
        
        // Hex value and binary value
        output.append(" hex value :").append(hexString).append("\n");
        output.append(" binary value : ").append(binaryString).append("\n");
        
        // Unicode value in java file & web page with decimal encoding
        output.append(" unicode value (Base 10): ");
        output.append("\\u").append(i).append(";").append("\n");
        
        output.append(" unicode value (Base 10 in web page): ");
        output.append("&#").append(i).append(";").append("\n");
        
        // Unicode value in java file & web page with hexadecimal encoding
        output.append(" unicode value (Base 16): ");
        output.append("\\u").append(hexString).append(";").append("\n");
        
        output.append(" unicode value (Base 16 in web page): ");
        output.append("&#").append(hexString).append(";").append("\n");

        System.out.println(output.toString());
    }

}

 最终的测试结果如下：

 

Original String : 中文

Convert string to bytes array :
 byte[0]=-42
 byte[1]=-48
 byte[2]=-50
 byte[3]=-60

Start to convert by character:

Character : 中
 byte value : 45
 int value : 20013
 short value : 20013
 hex value :4e2d
 binary value : 100111000101101
 unicode value (Base 10): \u20013;
 unicode value (Base 10 in web page): 中
 unicode value (Base 16): \u4e2d;
 unicode value (Base 16 in web page): e2d;

Character : 文
 byte value : -121
 int value : 25991
 short value : 25991
 hex value :6587
 binary value : 110010110000111
 unicode value (Base 10): \u25991;
 unicode value (Base 10 in web page): 文
 unicode value (Base 16): \u6587;
 unicode value (Base 16 in web page): ᦻ
可以看到在Java中，字符的unicode有两种表示显示：一种是10进制形式，一种是16进制形式。它们可以分别通过：int i = (int)(string.charAt(i))和Integer.toHexString(i);获得。而且在java文件和Web页面，同一个unicode的表示形式是不同。web页面需要用&#进行转义，在java文件中则使用\u进行转义。