我已经设置了datasource,在web层运行就能获得连接显示数据,而jbuilder环境下在main方法中直接运行就获不到连接呢?public class DBConnectionManager {
private static DBConnectionManager dbc = null;
public static synchronized DBConnectionManager getInstance() {
if (dbc == null) {
dbc = new DBConnectionManager();
}
return dbc;
}
/**
* 获取上下文
* @throws NamingException
* @return Context
*/
private Context getInitialContext() throws NamingException {
Hashtable environment = new Hashtable();
environment.put(Context.INITIAL_CONTEXT_FACTORY, "org.jnp.interfaces.NamingContextFactory");
environment.put(Context.URL_PKG_PREFIXES, "org.jboss.naming:org.jnp.interfaces");
environment.put(Context.PROVIDER_URL, "jnp://127.0.0.1:1099");
return new InitialContext(environment);
}
/**.
* 获取连接
*/
public Connection getConnection(String dataSourceName) {
DataSource ds = null;
Connection conn = null;
try {
InitialContext ctx = getInitialContext();
ds = (DataSource) ctx.lookup(dataSourceName);
return conn;
}
catch (Exception ex) {
}
return null;
}
public ResultSet rs_row(){
Connection conn = DBConnectionManager.getInstance().getConnection("java:/ntsky");
System.out.println("conn = " + conn);
String sql = "select * from t_user";
ResultSet rs = null;
try {
Statement stmt = conn.createStatement();
rs = stmt.executeQuery(sql);
return rs;
}
catch (Exception ex) {
System.out.println("ex"+ex.getMessage());
}
finally{
try {
conn.close();
}
catch (Exception e) {
// logger.error("DB conn 关闭数据库连接错误 " + e.getMessage());
}
}
return null;
}
public static void main(String[] args) {
DBConnectionManager dbcm = new DBConnectionManager();
ResultSet rs = dbcm.rs_row();
try{
System.out.println("1 : " + rs.getString(1));
}
catch(Exception e){
System.out.println("main "+e.getMessage());
}
}
}
