java blob類型和字符串轉換

package test;

import java.sql.Blob;
import java.sql.Clob;

import javax.sql.rowset.serial.SerialBlob;
import javax.sql.rowset.serial.SerialClob;

public class Hello {
    public static void main(String[] args) {
        String str="123456";
        //也可以這樣不傳字符集名稱，默認使用系統的
        //Blob blob = new SerialBlob(str.getBytes());
        //clob 轉 String
        String clobToString="";
        //blob 轉 String
        String blobToString="";
        try {
            //String 轉 clob
            Clob clob = new SerialClob(str.toCharArray());
            //String 轉 blob
            Blob blob = new SerialBlob(str.getBytes("GBK"));
            clobToString = clob.getSubString(1, (int) clob.length());
            blobToString = new String(blob.getBytes(1, (int) blob.length()), "GBK");
        } catch (Exception e) {
            // TODO: handle exception
            System.err.println("======="+e.getMessage());
        }
        
        //前面若沒傳入字符集名稱，則這裏也不需要傳入，以免出錯
        //String blobString = new String(blob.getBytes(1, (int) blob.length()));
        
        System.out.println(clobToString);
        System.out.println(blobToString);
    }
}