/**
* Determine whether or a not a User with the supplied researcherID exists
*
* @param username The researcherID to test
* @return true if the user exists, false if not
* @throws SQLException if a database error was encountered
*/
public static boolean userExists(int researcherID) throws SQLException {
boolean returnVal = false;
// Get our connection to the database.
Connection conn = DBConnectionManager.getConnection("yrc");
PreparedStatement stmt = null;
ResultSet rs = null;
try {
stmt = conn.prepareStatement("SELECT researcherID FROM tblUsers WHERE researcherID = ?");
stmt.setInt(1, researcherID);
rs = stmt.executeQuery();
// No rows returned.
if (!rs.next()) {
returnVal = false;
} else {
returnVal = true;
}
rs.close();
rs = null;
stmt.close();
stmt = null;
conn.close();
conn = null;
} finally {
// Always make sure result sets and statements are closed,
// and the connection is returned to the pool
if (rs != null) {
try {
rs.close();
} catch (SQLException e) {;
}
rs = null;
}
if (stmt != null) {
try {
stmt.close();
} catch (SQLException e) {;
}
stmt = null;
}
if (conn != null) {
try {
conn.close();
} catch (SQLException e) {;
}
conn = null;
}
}
return returnVal;
}
/**
* 获得数据库连接
*
* @return : 一个连接
*/
public void getConnection() {
if (conn == null) {
try {
conn = dbManager.getConnection();
} catch (SQLException ex) {
Debug.getAppErrLogger().error("取数据库连接错误!", ex);
}
}
}
/** 释放数据库连接 */
public void close() {
if (conn != null) {
try {
dbManager.freeConnection(conn);
conn = null;
} catch (SQLException ex) {
Debug.getAppErrLogger().error("释放数据库连接错误!", ex);
}
}
}
/**
* Determine whether or a not a Researcher with the supplied email exists
*
* @param email The email to test
* @return The researcher ID of the researcher if it exists, -1 if it doesn't
* @throws SQLException if a database error was encountered
*/
public static int emailExists(String email) throws SQLException {
int returnVal = -1;
if (email == null || email.equals("")) {
return -1;
}
// Get our connection to the database.
Connection conn = DBConnectionManager.getConnection("yrc");
PreparedStatement stmt = null;
ResultSet rs = null;
try {
stmt =
conn.prepareStatement(
"SELECT researcherID FROM tblResearchers WHERE researcherEmail = ?");
stmt.setString(1, email);
rs = stmt.executeQuery();
// No rows returned.
if (!rs.next()) {
returnVal = -1;
} else {
returnVal = rs.getInt("researcherID");
}
rs.close();
rs = null;
stmt.close();
stmt = null;
conn.close();
conn = null;
} finally {
// Always make sure result sets and statements are closed,
// and the connection is returned to the pool
if (rs != null) {
try {
rs.close();
} catch (SQLException e) {;
}
rs = null;
}
if (stmt != null) {
try {
stmt.close();
} catch (SQLException e) {;
}
stmt = null;
}
if (conn != null) {
try {
conn.close();
} catch (SQLException e) {;
}
conn = null;
}
}
return returnVal;
}
/**
* Get a populated User object corresponding to a username.
*
* @param username The username to test
* @return The User object corresponding to that username.
* @throws NoSuchUserException if that username does not exist.
* @throws SQLException if a database error was encountered.
*/
public static User getUser(String username) throws NoSuchUserException, SQLException {
// The User to return
User theUser;
// Make sure the username isn't null
if (username == null) {
throw new NoSuchUserException("got null for username in UserUtils.getUser");
}
// Get our connection to the database.
Connection conn = DBConnectionManager.getConnection("yrc");
PreparedStatement stmt = null;
ResultSet rs = null;
try {
stmt = conn.prepareStatement("SELECT researcherID FROM tblUsers WHERE username = ?");
stmt.setString(1, username);
rs = stmt.executeQuery();
// No rows returned.
if (!rs.next()) {
throw new NoSuchUserException("Username not found.");
}
theUser = new User();
try {
theUser.load(rs.getInt("researcherID"));
} catch (InvalidIDException e) {
throw new NoSuchUserException(
"Somehow, we got an invalid ID ("
+ rs.getInt("researcherID")
+ ") after we got the ID from the username... This can't be good.");
}
rs.close();
rs = null;
stmt.close();
stmt = null;
conn.close();
conn = null;
} finally {
// Always make sure result sets and statements are closed,
// and the connection is returned to the pool
if (rs != null) {
try {
rs.close();
} catch (SQLException e) {;
}
rs = null;
}
if (stmt != null) {
try {
stmt.close();
} catch (SQLException e) {;
}
stmt = null;
}
if (conn != null) {
try {
conn.close();
} catch (SQLException e) {;
}
conn = null;
}
}
return theUser;
}