分类：Java

利用EclipseLink 输出jpa sql

Posted on by admin 
//java code如下

       TypedQuery<?> outputSql = entityManager.createQuery(query);

        org.eclipse.persistence.sessions.Session session = communityEm.unwrap(org.eclipse.persistence.jpa.JpaEntityManager.class).getActiveSession();

        org.eclipse.persistence.queries.DatabaseQuery databaseQuery = outputSql.unwrap(org.eclipse.persistence.jpa.JpaQuery.class).getDatabaseQuery();

        databaseQuery.prepareCall(session, new org.eclipse.persistence.sessions.DatabaseRecord());

        System.out.println("databaseQuery.getSQLString()"+databaseQuery.getSQLString());

Java 小知识

Posted on by admin

1. Get client timezone

Calendar.getInstance().getTimeZone()

2. JPA sql 输出

//queryType:TypedQuery 
System.out.println(queryType.unwrap(org.eclipse.persistence.jpa.JpaQuery.class).getDatabaseQuery().getSQLString());


3. LocalDateTime to Date


//local_time : LocalDateTime
Date.from( local_time.atZone( ZoneId.systemDefault()).toInstant());

Java 脚本连接hana 数据库

Posted on by admin

请见如下code:获取hana kernel信息 和 license 信息
请 google ‘ngdbc jar’ 或直接下载附件zip包，解压后引用jar包即可 连接hana驱动jar

import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;

	static void query_info(String ip, String port, String tename, String user, String password) {
		String perline = "";
		Connection connection = null;
		String hostname = null;
		String lisdate = null;
		String liedate = null;
		String version = null;
		String kernel = null;
		try {

			Class.forName("com.sap.db.jdbc.Driver");
			String url = "jdbc:sap://" + ip + ":" + port + "/" + tename + ""; 

			connection = java.sql.DriverManager.getConnection(url, user, password);

			System.out.println("Connection done");

		} catch (Exception e) {
			System.err.println(ip + " Connection failed!" + e.getMessage());
		}

		if (connection != null) {
			try {
				System.out.println(ip + "  Connection to HANA successful!");

				// query license start/end date
				Statement stmt = connection.createStatement();
				ResultSet resultSet = stmt.executeQuery("select * from SYS.M_LICENSE ");

				resultSet.next();
				lisdate = resultSet.getString("START_DATE");
				liedate = resultSet.getString("EXPIRATION_DATE");

				System.out.println(lisdate);
				System.out.println(liedate);

				// query version info
				stmt = connection.createStatement();
				resultSet = stmt.executeQuery("select value from SYS.M_SYSTEM_OVERVIEW where name='Version'");

				resultSet.next();
				version = resultSet.getString("value");

				// query kernel info
				stmt = connection.createStatement();
				resultSet = stmt
						.executeQuery("select host,value from SYS.M_HOST_INFORMATION where key='os_kernel_version'");

				resultSet.next();
				kernel = resultSet.getString("value");
				hostname = resultSet.getString("host");

				System.out.println(version);
				System.out.println(kernel);
				System.out.println(hostname);

				resultSet.close();
				stmt.close();
				connection.close();


			} catch (SQLException e) {
				System.err.println("Query failed!" + e.getMessage());
			}
		}

	}