Mybatis源码阅读之DatabaseFactory

package org.apache.ibatis.metadata;

 

import java.sql.Connection;

import java.sql.DatabaseMetaData;

import java.sql.ResultSet;

import java.sql.SQLException;

 

public class DatabaseFactory {

  private DatabaseFactory() {

  }

 

  public static Database newDatabase(Connection conn, String catalogFilter, String schemaFilter) throws SQLException {

    Database database = new Database(catalogFilter, schemaFilter);

    ResultSet rs = null;

    try {

      DatabaseMetaData dbmd = conn.getMetaData();

 

      try {

        rs = dbmd.getColumns(catalogFilter, schemaFilter, null, null);

        while (rs.next()) {

          String catalogName = rs.getString("TABLE_CAT");

          String schemaName = rs.getString("TABLE_SCHEM");

          String tableName = rs.getString("TABLE_NAME");

          String columnName = rs.getString("COLUMN_NAME");

          int dataType = Integer.parseInt(rs.getString("DATA_TYPE"));

          Table table = database.getTable(tableName);

          if (table == null) {

            table = new Table(tableName);

            table.setCatalog(catalogName);

            table.setSchema(schemaName);

            database.addTable(table);

          }

          table.addColumn(new Column(columnName, dataType));

        }

      } finally {

        if (rs != null) rs.close();

      }

 

      try {

        String[] tableNames = database.getTableNames();

        for (int i = 0; i < tableNames.length; i++) {

          Table table = database.getTable(tableNames[i]);

          rs = dbmd.getPrimaryKeys(catalogFilter, schemaFilter, table.getName());

          if (rs.next()) {

            String columnName = rs.getString("COLUMN_NAME");

            table.setPrimaryKey(table.getColumn(columnName));

          }

        }

      } finally {

        if (rs != null) rs.close();

      }

 

    } finally {

      try {

        conn.rollback();

      } catch (Exception e) { /*ignore*/ }

    }

    return database;

  }

 

}