import java.util.Arrays;
import java.util.List;

public class GenerateColumns {

    public static final String DOT = ".";
    public static final String BLANK = " ";
    public static final String COMMA = ",";
    public static String originalColumns = "ID,EMP_NO,EMP_NAME,SALARY";
    public static String newColumns = "E_ID,E_EMP_NO,E_EMP_NAME,E_SALARY";
    
    public static void main(String[] args) {
        String sql = generateSql("emp", "e");
        System.out.println(sql);
        String xmlStr = generateMyBatisXml(newColumns);
        System.out.println(xmlStr);
    }
    
    public static String generateMyBatisXml(String newColumns) {
        String xmlStr = "";
        String[] newColumnArr = newColumns.split(",");
        List<String> newColumnList = Arrays.asList(newColumnArr);
        for(int i = 0; i < newColumnList.size(); i++) {
            String currentXmlStr = "<result column=\"" 
                    + newColumnList.get(i).toUpperCase()
                    + "\""
                    + BLANK 
                    + "jdbcType=\"VARCHAR\""
                    + BLANK
                    + "property=\""
                    + newColumnList.get(i).toUpperCase()
                    + "\"/>"
                    + "\r\n";
            xmlStr += currentXmlStr;
        }
        return xmlStr;
    }
    
    public static String generateSql(String tableName, String tableAbbr){
        String sql = "SELECT" + BLANK;
        String[] originalColumnArr = originalColumns.split(",");
        List<String> originalColumnList = Arrays.asList(originalColumnArr);
        String[] newColumnArr = newColumns.split(",");
        List<String> newColumnList = Arrays.asList(newColumnArr);
        if(originalColumnList.size() == newColumnList.size()) {
            for(int i = 0; i < originalColumnList.size(); i++) {
                sql += tableAbbr.toUpperCase() + DOT 
                    + originalColumnList.get(i).toUpperCase()
                    + BLANK 
                    + newColumnList.get(i).toUpperCase()
                    + COMMA;
            }
            sql = sql.substring(0, sql.length() - 1);
            sql += BLANK + "FROM" + BLANK + tableName.toUpperCase()
                + BLANK
                + tableAbbr.toUpperCase();
        }
        return sql;
    }

}