JDBC MySQL接続クラス(2007/11/13(火) 23:12:25)

MySQL Clusterの負荷テストの際に使用したMySQLを簡単に書くためのクラス。

勘違いもいっぱいありそうやけど、初めてのJDBC。

import java.sql.*;

public class MySQL {
    private String url = "localhost";
    private int    prt = 3306;
    private String usr = "root";
    private String pwd = "password";
    private String dbn = "";

    private Connection con = null;
    private Statement stmt = null;

    private ResultSet resultSet = null;
    private int updateCount = -1;

    MySQL(){
        try{
            Class.forName("com.mysql.jdbc.Driver");
        }catch(ClassNotFoundException e){
            e.printStackTrace();
        }
    }

    MySQL(String url, int port, String usr, String pwd, String dbn){
        this();

        this.url = url;
        this.prt = prt;
        this.usr = usr;
        this.pwd = pwd;
        this.dbn = dbn;
    }

    public int getUpdateCount(){
        return this.updateCount;
    }

    public ResultSet getResultSet(){
        return this.resultSet;
    }

    public boolean connect(){
        try{
            // データベースへ接続
            con = DriverManager.getConnection("jdbc:mysql://" + url + ":" + prt + "/" + dbn + "?useUnicode=true", usr, pwd);
            return true;
        }catch(SQLException e){
            e.printStackTrace();
        }
        return false;
    }

    public boolean deconnect(){
        try{
            if(this.con != null){
                this.con.rollback();
                this.con.rollback();
            }
            if(this.stmt != null){
                this.stmt.close();
            }
            if(this.con != null){
                this.con.close();
            }
            return true;
        }catch(SQLException se){
            se.printStackTrace();
        }
        return false;
    }

    public boolean startTransaction(){
        try{
            this.stmt = this.con.createStatement();
            this.con.setAutoCommit(false);
            return true;
        }catch(SQLException e){
            try{
                if(this.con != null){
                    this.con.rollback();
                }
            }catch(SQLException se){
                se.printStackTrace();
            }
            e.printStackTrace();
        }
        return false;
    }

    public boolean commit(){
        try{
            if(this.con != null){
                this.con.commit();
            }
            return true;
        }catch(SQLException e){
            e.printStackTrace();
        }
        return false;
    }

    public boolean rollback(){
        try{
            if(this.con != null){
                this.con.rollback();
            }
            return true;
        }catch(SQLException e){
            e.printStackTrace();
        }
        return false;
    }

    public boolean runExecute(String sql) throws SQLException{
        //System.out.println("SQL : " + sql);
        boolean isResult = this.stmt.execute(sql);
        int rowCount = this.stmt.getUpdateCount();

        //更新系クエリ結果
        if(rowCount >= 0) {
            this.updateCount = rowCount;
            this.resultSet = null;
            return false;
        }
        //Select系クエリ結果
        else {
            this.updateCount = -1;
            this.resultSet = this.stmt.getResultSet();
            return true;
        }
    }

    public void addBatch(String sql) throws SQLException{
        //System.out.println("SQL : " + sql);
        this.stmt.addBatch(sql);
    }

    public int[] runBatch() throws SQLException{
        return this.stmt.executeBatch();
    }

    public int runUpdate(String sql) throws SQLException{
        //System.out.println("SQL : " + sql);
        this.updateCount = this.stmt.executeUpdate(sql);
        this.resultSet = null;
        return this.updateCount;
    }

    public ResultSet runQuery(String sql) throws SQLException{
        //System.out.println("SQL : " + sql);
        this.updateCount = -1;
        this.resultSet = this.stmt.executeQuery(sql);
        return this.resultSet;
    }

    public static void printResultSet(ResultSet rs) throws SQLException{
        ResultSetMetaData md = rs.getMetaData();
        //カラム
        writeLine(md);
        for(int i = 1; i <= md.getColumnCount(); i++){
            String col = md.getColumnName(i);
            System.out.print("|");
            System.out.print(col);
            for(int j = 0; j < md.getColumnDisplaySize(i) - col.toCharArray().length; j++){
                System.out.print(" ");
            }
        }
        System.out.println("|");
        writeLine(md);

        //データ
        while(rs.next()){
            for(int i = 1; i <= md.getColumnCount(); i++){
                String val = rs.getString(md.getColumnName(i));
                System.out.print("|" + val);
                for(int j = 0; j < md.getColumnDisplaySize(i) - val.toCharArray().length; j++){
                    System.out.print(" ");
                }
            }
            System.out.println("|");
        }
        writeLine(md);
        System.out.println("");
    }

    public static void writeLine(ResultSetMetaData md) throws SQLException{
        String line = "+";
        for(int i = 1; i <= md.getColumnCount(); i++){
            for(int j = 0; j < md.getColumnDisplaySize(i); j++){
                line += "-";
            }
            line += "+";
        }
        System.out.println(line);
    }

    public static int getRowSize(ResultSet rs) throws SQLException{
        int row = rs.getRow();
        rs.last();
        int size = rs.getRow();
        if(row == 0){
            rs.first();
        }
        else{
            rs.absolute(row);
        }
        return size;
    }
}