Running the COPY FROM STDIN Statement to Import Data

public class CopyManager
extends Object

public CopyManager(BaseConnection connection)
throws SQLException

import java.sql.Connection;
import java.sql.DriverManager;
import java.io.IOException;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.sql.SQLException;
import org.opengauss.copy.CopyManager;
import org.opengauss.core.BaseConnection;

public class Copy{

     public static void main(String[] args)
     {
      String urls = new String("jdbc:opengauss://localhost:8000/postgres"); // URL of the database
      String username = new String("username");            // Username
      String password = new String("passwd");             // Password
      String tablename = new String("migration_table"); // Table information
      String tablename1 = new String("migration_table_1"); // Table information
      String driver = "org.opengauss.Driver";
      Connection conn = null;

      try {
          Class.forName(driver);
          conn = DriverManager.getConnection(urls, username, password);
      } catch (ClassNotFoundException e) {
           e.printStackTrace(System.out);
      } catch (SQLException e) {
           e.printStackTrace(System.out);
      }

      // Export data from the migration_table table to the d:/data.txt file.
      try {
          copyToFile(conn, "d:/data.txt", "(SELECT * FROM migration_table)");
      } catch (SQLException e) {
          // TODO Auto-generated catch block
          e.printStackTrace();
      } catch (IOException e) {
          // TODO Auto-generated catch block
          e.printStackTrace();
      }
      // Import data from the d:/data.txt file to the migration_table_1 table.
      try {
          copyFromFile(conn, "d:/data.txt", tablename1);
      } catch (SQLException e) {
          // TODO Auto-generated catch block
          e.printStackTrace();
      } catch (IOException e) {
          // TODO Auto-generated catch block
          e.printStackTrace();
      }

      // Export data from the migration_table_1 table to the d:/data1.txt file.
      try {
          copyToFile(conn, "d:/data1.txt", tablename1);
      } catch (SQLException e) {
          // TODO Auto-generated catch block
          e.printStackTrace();
      } catch (IOException e) {
          // TODO Auto-generated catch block
          e.printStackTrace();
      }
  }

  public static void copyFromFile(Connection connection, String filePath, String tableName)
         throws SQLException, IOException {

     FileInputStream fileInputStream = null;

     try {
         CopyManager copyManager = new CopyManager((BaseConnection)connection);
         fileInputStream = new FileInputStream(filePath);
         copyManager.copyIn("COPY " + tableName + " FROM STDIN with (" + "DELIMITER"+"'"+ delimiter +  "'" + "ENCODING " + "'" + encoding + "')", fileInputStream);
     } finally {
         if (fileInputStream != null) {
             try {
                 fileInputStream.close();
             } catch (IOException e) {
                 e.printStackTrace();
             }
         }
     }
 }
     public static void copyToFile(Connection connection, String filePath, String tableOrQuery)
          throws SQLException, IOException {

      FileOutputStream fileOutputStream = null;

      try {
          CopyManager copyManager = new CopyManager((BaseConnection)connection);
          fileOutputStream = new FileOutputStream(filePath);
          copyManager.copyOut("COPY " + tableOrQuery + " TO STDOUT", fileOutputStream);
      } finally {
          if (fileOutputStream != null) {
              try {
                  fileOutputStream.close();
              } catch (IOException e) {
                  e.printStackTrace();
              }
          }
      }
  }
}

import java.io.StringReader;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;

import org.opengauss.copy.CopyManager;
import org.opengauss.core.BaseConnection;

public class Migration{

    public static void main(String[] args) {
        String url = new String("jdbc:opengauss://localhost:8000/postgres"); // URL of the database
        String user = new String("username");            // MogDB database user name
        String pass = new String("passwd");             // MogDB database password
        String tablename = new String("migration_table_1"); // Table information
        String delimiter = new String("|");              // Delimiter
        String encoding = new String("UTF8");            // Character set
        String driver = "org.opengauss.Driver";
        StringBuffer buffer = new StringBuffer();       // Buffer to store formatted data

        try {
            // Obtain the query result set of the source database.
            ResultSet rs = getDataSet();

            // Traverse the result set and obtain records row by row.
            // The values of columns in each record are separated by the specified delimiter and end with a linefeed, forming strings.
            // Add the strings to the buffer.
            while (rs.next()) {
                buffer.append(rs.getString(1) + delimiter
                        + rs.getString(2) + delimiter
                        + rs.getString(3) + delimiter
                        + rs.getString(4)
                        + "\n");
            }
            rs.close();

            try {
                // Connect to the target database.
                Class.forName(driver);
                Connection conn = DriverManager.getConnection(url, user, pass);
                BaseConnection baseConn = (BaseConnection) conn;
                baseConn.setAutoCommit(false);

                // Initialize the table.
                String sql = "Copy " + tablename + " from STDIN with (DELIMITER " + "'" + delimiter + "'" +","+ " ENCODING " + "'" + encoding + "'");

                // Commit data in the buffer.
                CopyManager cp = new CopyManager(baseConn);
                StringReader reader = new StringReader(buffer.toString());
                cp.copyIn(sql, reader);
                baseConn.commit();
                reader.close();
                baseConn.close();
            } catch (ClassNotFoundException e) {
                e.printStackTrace(System.out);
            } catch (SQLException e) {
                e.printStackTrace(System.out);
            }

        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    //********************************
    // Return the query result set from the source database.
    //*********************************
    private static ResultSet getDataSet() {
        ResultSet rs = null;
        try {
            Class.forName("com.MY.jdbc.Driver").newInstance();
            Connection conn = DriverManager.getConnection("jdbc:MY://10.119.179.227:3306/jack?useSSL=false&allowPublicKeyRetrieval=true", "jack", "Enmo@123");
            Statement stmt = conn.createStatement();
            rs = stmt.executeQuery("select * from migration_table");
        } catch (SQLException e) {
            e.printStackTrace();
        } catch (Exception e) {
            e.printStackTrace();
        }
        return rs;
    }
}