/**
* Creates a HiveQL external table.
*
* @param query
* @return True if the table could be created, false otherwise.
*/
public boolean doCreateTable(String query) {
Connection con = null;
Statement stmt = null;
ResultSet rs = null;
boolean res = true;
try {
// get a connection to the Hive/Shark server
con = getConnection();
// create a statement
stmt = con.createStatement();
// execute the query
rs = stmt.executeQuery(query);
} catch (Throwable e) {
LOGGER.error(
"Runtime error (The Hive table cannot be created. Hive query='"
+ query
+ "'. Details="
+ e.getMessage()
+ ")");
res = false;
} finally {
return res && closeHiveObjects(con, stmt, rs);
} // try catch finally
} // doCreateTable
/**
* Close all the Hive objects previously opened by doCreateTable and doQuery.
*
* @param con
* @param stmt
* @param rs
* @return True if the Hive objects have been closed, false otherwise.
*/
private boolean closeHiveObjects(Connection con, Statement stmt, ResultSet rs) {
boolean res = true;
if (con != null) {
try {
con.close();
} catch (SQLException e) {
LOGGER.error(
"Runtime error (The Hive connection could not be closed. Details="
+ e.getMessage()
+ ")");
res = false;
} // try catch // try catch
} // if
if (stmt != null) {
try {
stmt.close();
} catch (SQLException e) {
LOGGER.error(
"Runtime error (The Hive statement could not be closed. Details="
+ e.getMessage()
+ ")");
res = false;
} // try catch // try catch
} // if
if (rs != null) {
try {
rs.close();
} catch (SQLException e) {
LOGGER.error(
"Runtime error (The Hive result set could not be closed. Details="
+ e.getMessage()
+ ")");
res = false;
} // try catch // try catch
} // if
return res;
} // closeHiveObjects
/**
* Executes a HiveQL sentence.
*
* @param query
* @return True if the query succeded, false otherwise.
*/
public boolean doQuery(String query) {
Connection con = null;
Statement stmt = null;
ResultSet rs = null;
boolean res = true;
try {
// get a connection to the Hive/Shark server
con = getConnection();
// create a statement
stmt = con.createStatement();
// execute the query
rs = stmt.executeQuery(query);
// iterate on the result
while (rs.next()) {
String s = "";
for (int i = 1; i < rs.getMetaData().getColumnCount(); i++) {
s += rs.getString(i) + ",";
} // for
s += rs.getString(rs.getMetaData().getColumnCount());
} // while
} catch (Throwable e) {
LOGGER.error(
"Runtime error (The Hive query cannot be executed. Hive query='"
+ query
+ "'. Details="
+ e.getMessage()
+ ")");
res = false;
} finally {
return res && closeHiveObjects(con, stmt, rs);
} // try catch finally
} // doQuery
/**
* Gets a connection to the Hive server.
*
* @return
* @throws Exception
*/
private Connection getConnection() throws Exception {
// dynamically load the Hive JDBC driver
Class.forName(DRIVERNAME);
// return a connection based on the Hive JDBC driver
LOGGER.debug(
"Connecting to jdbc:hive://"
+ hiveServer
+ ":"
+ hivePort
+ "/default?user="******"&password=XXXXXXXXXX");
return DriverManager.getConnection(
"jdbc:hive://"
+ hiveServer
+ ":"
+ hivePort
+ "/default?user="******"&password="
+ hadoopPassword);
} // getConnection