Question

我有一个带有“ spring boot”的应用程序，我需要连接到新的Mysql数据库以读取表。一切正常，我不知道这是否是最好的方法以及如何进行分页。

//我的连接

package com.xxx.xxx.config;

import java.sql.Connection;
import java.sql.SQLException;

import com.zaxxer.hikari.HikariConfig;
import com.zaxxer.hikari.HikariDataSource;

public class DatabaseAsteriskConfiguration {

private static HikariConfig config = new HikariConfig();
private static HikariDataSource ds;

static {
    config.setJdbcUrl("jdbc:mysql://xxxxxx/db");
    config.setUsername("xxxx");
    config.setPassword("xxx");
    config.addDataSourceProperty("cachePrepStmts", "true");
    config.addDataSourceProperty("prepStmtCacheSize", "250");
    config.addDataSourceProperty("prepStmtCacheSqlLimit", "2048");
    ds = new HikariDataSource(config);
}

public DatabaseAsteriskConfiguration() {
}

public static Connection getConnection() throws SQLException {
    return ds.getConnection();
}
}

//我的仓库

package com.xxxx.xxxx.asterisk;

import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.ArrayList;
import java.util.List;

import org.springframework.stereotype.Repository;

import com.abalia.elser2.config.DatabaseAsteriskConfiguration;

@Repository
public class AsteriskRepository {

Connection conn = null;
Statement stmt = null;
List<AsteriskDTO> list = new ArrayList<>();

public List<AsteriskDTO> loadAll(String inicio, String fin) {
    Connection conn = null;
    Statement stmt = null;
    try {
        // STEP 2: Register JDBC driver
        Class.forName("com.mysql.jdbc.Driver");

        // STEP 3: Open a connection
        System.out.println("Connecting to database...");
        conn = DatabaseAsteriskConfiguration.getConnection();

        // STEP 4: Execute a query
        System.out.println("Creating statement...");
        stmt = conn.createStatement();
        String sql;
        sql = "SELECT * FROM cdr WHERE calldate >= '" + inicio + "' and calldate <= '" + fin + "'";
        ResultSet rs = stmt.executeQuery(sql);

        // STEP 5: Extract data from result set
        while (rs.next()) {
            AsteriskDTO dto = new AsteriskDTO();
            dto.setSrc(rs.getString("src"));
            dto.setDst(rs.getString("dst"));
            dto.setDuration(rs.getInt("duration"));
            dto.setCalldate(rs.getTimestamp("calldate"));

            // Display values
            System.out.println("src: " + dto.getSrc() + "calldate: " + dto.getCalldate());
            list.add(dto);
        }
        // STEP 6: Clean-up environment
        rs.close();
        stmt.close();
        conn.close();
        return list;
    } catch (SQLException se) {
        // Handle errors for JDBC
        se.printStackTrace();
    } catch (Exception e) {
        // Handle errors for Class.forName
        e.printStackTrace();
    } finally {
        // finally block used to close resources
        try {
            if (stmt != null)
                stmt.close();
        } catch (SQLException se2) {
        } // nothing we can do
        try {
            if (conn != null)
                conn.close();
        } catch (SQLException se) {
            se.printStackTrace();
        } // end finally try
    }
    return list;
}

}

有人可以帮助我，如何以最佳方式连接不是主要应用程序的BBDD并与之交互，以及如何进行分页。

外部连接和分页。春季靴

0 个答案: