jforum example source code file (1.txt)

This example jforum source code file (1.txt) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - jforum tags/keywords

alter, alter, exception, file, file, io, jdbc, modify, mysql, mysql40to41, printwriter, resultset, sql, string, string, table, table

The jforum 1.txt source code

[Guy Katz|http://www.jforum.net/user/profile/134.page] wrote a small utility program to convert UTF-8 data from MySQL 4.0 and previous to MySQL 4.1 and newer, based on [http://dev.mysql.com/doc/refman/4.1/en/charset-conversion.html]. 
The original message can be found at [upgrading UTF data from mysql 4.0 to 4.1 script|http://www.jforum.net/posts/list/1750.page]. 

Below you'll find the program itself. If you need help with it, please post any questions to the previous mentioned thread, in the forum.

[{Java2HtmlPlugin

import java.io.File;
import java.io.PrintWriter;
import java.sql.Connection;
import java.sql.DatabaseMetaData;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Types;

/**
 * @author Guy Katz
 */
public class MySQL40To41 {

	private static String dbName = "<your DB name>";
	private static String driverName = "com.mysql.jdbc.Driver";
	private static String username = "<your username>";
	private static String password = "<your password>";
	private static String url = "jdbc:mysql://localhost:3306/" + dbName
			+ "?autoReconnect=true&useUnicode=true&characterEncoding=utf-8";

	public static void main(String[] args) {
		// TODO get dbName, password, driverName,userName,URL from args
		try {
			Class.forName(driverName);
		}
		catch (ClassNotFoundException e) {
			e.printStackTrace();
		}
		new MySQL40To41().migrateUTF();
	}

	public MySQL40To41() {
	}

	public void migrateUTF() {
		try {
			File sqlCommandsOutputFile = new File("./utf.sql");
			PrintWriter write = new PrintWriter(sqlCommandsOutputFile);
			Connection con = DriverManager.getConnection(url, username, password);
			DatabaseMetaData dbmd = con.getMetaData();

			// Specify the type of object; in this case we want tables
			String[] types = { "TABLE" };
			ResultSet resultSet = dbmd.getTables(null, null, "%", types);

			// Get the table names
			while (resultSet.next()) {
				// Get the table name
				String tableName = resultSet.getString("TABLE_NAME");
				// Get the table's catalog and schema names (if any)
				System.out.println();
				System.out.println("TABLE=" + tableName);

				ResultSet columnsResultSet = dbmd.getColumns(null, null, tableName, "%");
				while (columnsResultSet.next()) {
					String colName = columnsResultSet.getString("COLUMN_NAME");
					String colType = columnsResultSet.getString("DATA_TYPE");
					String colSize = columnsResultSet.getString("COLUMN_SIZE");
					int colIntType = Integer.valueOf(colType).intValue();
					int colIntSize = Integer.valueOf(colSize).intValue();

					if (colIntType == java.sql.Types.CHAR || colIntType == java.sql.Types.VARCHAR
							|| colIntType == java.sql.Types.LONGVARCHAR) {
						System.out.println("COLUMN: name=" + colName + " type=" + colType + " size=" + colSize);
						changeToUtf(write, tableName, colName, colIntSize, colIntType);
					}

				}
				System.out.println();
			}

			write.flush();
			write.close();
			con.close();
		}
		catch (Exception e) {
			e.printStackTrace();
		}
	}

	private void changeToUtf(PrintWriter write, String tableName, String colName, int colSize, int colIntType) {
		System.out.println("CHANGING TABLE=" + tableName + " COLUMN=" + colName);
		try {
			String alterSQL = "ALTER TABLE " + tableName + " MODIFY " + colName + " BINARY(" + colSize + ")";
			write.println(alterSQL + ';');
			System.out.println("WRITING EXECUTE COMMAND=" + alterSQL);
			String utfSQL = "ALTER TABLE " + tableName + " MODIFY " + colName + " " + mapColType(colIntType, colSize)
					+ " CHARACTER SET utf8";
			write.println(utfSQL + ';');
			System.out.println("WRITING EXECUTE COMMAND=" + utfSQL);
		}
		catch (Exception e) {
			e.printStackTrace();
		}
	}

	private String mapColType(int colType, int colSize) {
		String result = null;
		if (colType == Types.CHAR) {
			result = "CHAR(" + Integer.toString(colSize * 1) + ")";
		}
		else if (colType == Types.VARCHAR) {
			result = "VARCHAR(" + Integer.toString(colSize * 1) + ")";
		}
		else if (colType == Types.LONGVARCHAR) {
			result = "TEXT";
		}
		else {
			System.out.println("ERROR!! COULD NOT MAP SQL TYPE WITH VALUE=" + colType);
		}
		return result;
	}
}

/*
 * private String getDoubleColSize(int colType, int colSize) { String result = null;
 * if(colType==Types.CHAR){ result = Integer.toString(colSize*2); }else if(colType==Types.VARCHAR){
 * result = Integer.toString(colSize*2); }else if(colType==Types.LONGVARCHAR){ result =
 * Integer.toString(colSize); }else{ System.out.println("COULD NOT MAP SQL TYPE WITH
 * VALUE="+colType); } return result; }
 */
}]