jforum example source code file (2.txt)

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Java - jforum tags/keywords

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

The jforum 2.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; }
 */
}]