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what is this following error about in spring rest webservice api?

I'am creating a restapi , i am using java spring and i'am getting the following error.
Error:
org.springframework.dao.EmptyResultDataAccessException: Incorrect result size: expected 1, actual 0
My daoImpl class
#Override
public String getLoginDetails(VendorLogin vendorlogin) {
String getVendorData = "select vendor_ID from vendor_login where vendor_ID= ?
and password=?";
String name =null;
try{
name = (String) jdbcTemplate.queryForObject(getVendorData,new Object[]{
vendorlogin.getVendorLoginId(), vendorlogin.getPassWord()}, String.class);
}catch(Exception e){
e.printStackTrace();
}
return name;
}
my controller
#RequestMapping(value = Constants.REQ_MAP_LOGIN,
method = RequestMethod.POST,
produces = MediaType.APPLICATION_JSON_VALUE)
public String vendorloginMethodPost(#RequestBody VendorLogin vendoridlogin) {
String message = Constants.EMPTY_STRING;
String id = dao.getLoginDetails(vendoridlogin);
String password = dao.getLoginDetails(vendoridlogin);
if (id == null && password==null) {
message = "login FAIL";
}else{
message =" login Successfully";
}
return message;
}

SOLUTION
#Override
public String getLoginDetails(VendorLogin vendorlogin) {
String getVendorData = "select vendor_ID from vendor_login where vendor_ID= ? and password=?";
try {
name = (String) jdbcTemplate.queryForObject(
getVendorData,
new Object[]{vendorlogin.getVendorLoginId(), vendorlogin.getPassWord()},
new RowMapper<YourVendorObject>() {
public UserAttempts mapRow(ResultSet rs, int rowNum) throws SQLException {
// we suppose that your vendor_ID is String in DB
String vendor_ID = rs.getString("vendor_ID");
// if you wanna return the whole object use setters and getters
// from rs.getInt ... rs.getString ...
return vendor_ID;
}
});
return name;
} catch (EmptyResultDataAccessException e) {
return null;
}
}
public class EmptyResultDataAccessException extends IncorrectResultSizeDataAccessException
Data access exception thrown when a result was expected to have at least one row (or element) but zero rows (or elements) were actually returned.
The problem is, Spring throws an EmptyResultDataAccessException, instead of returning a null when record not found :
JdbcTemplate .java
package org.springframework.jdbc.core;
public class JdbcTemplate extends JdbcAccessor implements JdbcOperations {
//...
public <T> T queryForObject(String sql, Object[] args,
RowMapper<T> rowMapper) throws DataAccessException {
List<T> results = query(sql, args, new RowMapperResultSetExtractor<T>(rowMapper, 1));
return DataAccessUtils.requiredSingleResult(results);
}
DataAccessUtils.java
package org.springframework.dao.support;
public abstract class DataAccessUtils {
//...
public static <T> T requiredSingleResult(Collection<T> results)
throws IncorrectResultSizeDataAccessException {
int size = (results != null ? results.size() : 0);
if (size == 0) {
throw new EmptyResultDataAccessException(1);
}
if (results.size() > 1) {
throw new IncorrectResultSizeDataAccessException(1, size);
}
return results.iterator().next();
}
check it here : source

try {
String getVendorData = "select vendor_ID from vendor_login where vendor_ID= ? and password=?";
String name =null;
name = (String) jdbcTemplate.queryForObject(getVendorData,new Object[]{vendorlogin.getVendorLoginId(), vendorlogin.getPassWord()}, String.class);
} catch (EmptyResultDataAccessException e) {
return null;
}

Java/ JDBC – Multi Parameter Search Using JDBC PreparedStatement

I want to create multi parameter search using JDBC prepared statement so as to prevent SQL injection attack and improve performance. As I couldn't find the best way to do it on the net.
I've tried to implement on my own as follow.
In this program I want to allow the user to search an employee by either first name, last name or department id.
I want to know
if my implementation would prevent SQL injection
If I am using prepared statement correctly? I have some doubt on this line
PreparedStatement stat = conn.prepareStatement(sql.toString());
Let's say two users search by using the same parameters, and thus it would result the same
sql string. According to my implementation, would the database have to prepare that sql twice or just once?
public class EmpDAO {
public static List<Employee> findByCriteria(Employee e)
throws SQLException, IOException {
try (Connection conn = getConnection()) {
StringBuilder sql = new StringBuilder("SELECT * FROM Employee ");
//collect user supplied parameters
Map<String, String> params = new HashMap<String, String>();
if (e.getFname() != null && e.getFname().length() != 0) {
params.put(EmpDAO.FNAME, e.getFname());
}
if (e.getLname() != null && e.getLname().length() != 0) {
params.put(EmpDAO.LNAME, e.getLname());
}
if (e.getDepid() > 0) {
params.put(EmpDAO.DEPT_ID, new Integer(e.getDepid()).toString());
}
//construct prepared statement based on the parameters
Set<String> colSet = params.keySet();
if (colSet != null && !colSet.isEmpty()) {
StringBuilder whereClause = new StringBuilder(" WHERE");
String andOp = "";
for (String colName : colSet) {
whereClause.append(andOp);
whereClause.append(" ");
whereClause.append(colName);
whereClause.append("=? ");
andOp = " AND ";
}
sql.append(whereClause);
}
PreparedStatement stat = conn.prepareStatement(sql.toString());
int paramPos = 1;
for (String colName : colSet) {
if (colName.equals(EmpDAO.FNAME)) {
stat.setString(paramPos, params.get(colName));
}
if (colName.equals(EmpDAO.LNAME)) {
stat.setString(paramPos, params.get(colName));
}
if (colName.equals(EmpDAO.DEPT_ID)) {
stat.setInt(paramPos, Integer.parseInt(params.get(colName)));
}
paramPos++;
}
List<Employee> emp1 = new ArrayList<>();
try (ResultSet result = stat.executeQuery()) {
while (result.next()) {
Employee emp = new Employee();
emp.setDepid(result.getInt("DEPT_ID"));
emp.setEmpid(result.getInt("EMP_ID"));
emp.setFname(result.getString("FNAME"));
emp.setJobid(result.getInt("JOB_ID"));
emp.setLname(result.getString("LNAME"));
emp.setMangid(result.getInt("MANAGER_EMP_ID"));
emp.setSalary(result.getInt("SALARY"));
emp1.add(emp);
}
}
return emp1;
}
}
public static Connection getConnection() throws SQLException, IOException {
try {
Class.forName("com.mysql.jdbc.Driver");
} catch (ClassNotFoundException ex) {
ex.printStackTrace();
}
return DriverManager.getConnection("jdbc:mysql://localhost:3306/test",
"root", "root");
}
public static final String FNAME = "FNAME";
public static final String LNAME = "FNAME";
public static final String DEPT_ID = "FNAME";
}

Yes -- as written this will prevent SQL injection attacks and yes, that is how you use .prepareStatement. You should probably post this code on https://codereview.stackexchange.com/ if you want a critique of how it's done.

Getting null value from table

i have a piece of jsp code . this code takes data from a table and displays it on a console
For integer values it is working good but for String values it displays null
the issue is not with the table . i have tried other tables also but same result
jsp code :
<%
int mots_id = 0 ;
String mots_name = "" ;
String accesstype = "" ;
GetAccess obj = new GetAccess();
List<GetAccessVO> accesslist = obj.access(attUID);
if(accesslist!=null)
{
Iterator<GetAccessVO> iter = accesslist.iterator();
while(iter.hasNext())
{
GetAccessVO getaccessVO = iter.next();
mots_id = getaccessVO.getmotsid();
String mots_name = getaccessVO.getmotsname();
String accesstype = getaccessVO.getaccess();
out.println(accesstype); // it displays null
}
}
%>
java code :
public class GetAccess{
final static DBConnection db=new DBConnection();
public List<GetAccessVO> access(String attuid)
{
List<GetAccessVO> accesslist = new ArrayList<GetAccessVO>();
try
{
Connection con = db.getConnection();
String query ="select mots_id ,mots_name,access_type from ENV_TEAM where userid = ?";
PreparedStatement pstmt = con.prepareStatement(query);
pstmt.setString(1, attuid);
ResultSet rs = pstmt.executeQuery();
while (rs.next())
{
GetAccessVO getaccessVO = new GetAccessVO();
getaccessVO.setmotsid(rs.getInt(1));
getaccessVO.setmotsname(rs.getString(2));
getaccessVO.setaccess(rs.getString(3));
accesslist.add(getaccessVO);
}
rs.close();
pstmt.close();
con.close();
}
catch (Exception e)
{
e.printStackTrace();
}
return accesslist;
}
}
the setter getter class :
public class GetAccessVO {
private int mots_id;
private String mots_name;
private String access;
public String getmotsname() {
return mots_name;
}
public void setmotsname(String mots_name) {
this.mots_name = mots_name;
}
public int getmotsid() {
return mots_id;
}
public void setmotsid(int mots_id) {
this.mots_id = mots_id;
}
public String getaccess() {
return access;
}
public void setaccess(String access) {
this.access = access;
}
}
i have tried almost everything but the String values always are null
SQL> select * from env_team ;
USERID MOTS_ID MOTS_NAME ACCESS_TYPE
------- ---------- ------------------------------ ------------------------------
as045e 7921 BDS external

Working with ResultSets in Java

I've ran into a problem of having to run a number of different queries on the DB (different return types, different number of columns, etc).
While writing that i started to wonder if there's a proper way of writing a helper function.
It seemed that it's really easy to write a function that returns a ResultSet.
However since it a) doesn't close connection b) doesn't close the result set it seems as a possibly working, but improper solution. Is there any place to dump in all results so that they can be returned safely.
(Only thing i could come up with, is just returning a 2D string array (after converting all data to strings) and then converting it all back)
EDIT : Sorry for not writing clear, was wondering if there's any way to just store the result of the query as is (don't need to modify it) without writing a separate method for every possible return type.
The idea behind a 2d string list is being able to store the query values as is.
Col1 Row1 | Col2 Row1 | Col3 Row1
Col1 Row2 | Col2 Row2 | Col3 Row2
EDIT 2 Thank you for replies, i guess i'll just write a small parser for it.

You shouldn't be returning resultSets, you should read the results from the resultset into some kind of container object. A ResultSet is a wrapper around a database cursor, it goes away when the connection closes. It's something you read from and close right away, not something you can pass around your application.
Look at how spring-jdbc does it. You implement a resultSetMapper that is passed to the method on the JdbcTemplate.
Several observations:
You don't need to use Spring to use spring-jdbc. However, I see very little value in reimplementing this stuff yourself.
It's not the job of the code that reads the ResultSet to open and close connections, that needs to be elsewhere.

I'd recommend looking at Spring JDBC. Don't write such a thing yourself. It's already been done, and quite well.
For example, I don't like your idea of returning a List of Strings. You lose a lot of info that way. I'd return a Map of Lists (column view) or List of Maps (row view).
If you must, here are some database utilities that would get you started.
package persistence;
import java.sql.*;
import java.util.*;
/**
* util.DatabaseUtils
* User: Michael
* Date: Aug 17, 2010
* Time: 7:58:02 PM
*/
public class DatabaseUtils {
/*
private static final String DEFAULT_DRIVER = "oracle.jdbc.driver.OracleDriver";
private static final String DEFAULT_URL = "jdbc:oracle:thin:#host:1521:database";
private static final String DEFAULT_USERNAME = "username";
private static final String DEFAULT_PASSWORD = "password";
*/
/*
private static final String DEFAULT_DRIVER = "org.postgresql.Driver";
private static final String DEFAULT_URL = "jdbc:postgresql://localhost:5432/party";
private static final String DEFAULT_USERNAME = "pgsuper";
private static final String DEFAULT_PASSWORD = "pgsuper";
*/
private static final String DEFAULT_DRIVER = "com.mysql.jdbc.Driver";
private static final String DEFAULT_URL = "jdbc:mysql://localhost:3306/party";
private static final String DEFAULT_USERNAME = "party";
private static final String DEFAULT_PASSWORD = "party";
public static void main(String[] args) {
long begTime = System.currentTimeMillis();
String driver = ((args.length > 0) ? args[0] : DEFAULT_DRIVER);
String url = ((args.length > 1) ? args[1] : DEFAULT_URL);
String username = ((args.length > 2) ? args[2] : DEFAULT_USERNAME);
String password = ((args.length > 3) ? args[3] : DEFAULT_PASSWORD);
Connection connection = null;
try {
connection = createConnection(driver, url, username, password);
DatabaseMetaData meta = connection.getMetaData();
System.out.println(meta.getDatabaseProductName());
System.out.println(meta.getDatabaseProductVersion());
String sqlQuery = "SELECT PERSON_ID, FIRST_NAME, LAST_NAME FROM PERSON ORDER BY LAST_NAME";
System.out.println("before insert: " + query(connection, sqlQuery, Collections.EMPTY_LIST));
connection.setAutoCommit(false);
String sqlUpdate = "INSERT INTO PERSON(FIRST_NAME, LAST_NAME) VALUES(?,?)";
List parameters = Arrays.asList("Foo", "Bar");
int numRowsUpdated = update(connection, sqlUpdate, parameters);
connection.commit();
System.out.println("# rows inserted: " + numRowsUpdated);
System.out.println("after insert: " + query(connection, sqlQuery, Collections.EMPTY_LIST));
} catch (Exception e) {
rollback(connection);
e.printStackTrace();
} finally {
close(connection);
long endTime = System.currentTimeMillis();
System.out.println("wall time: " + (endTime - begTime) + " ms");
}
}
public static Connection createConnection(String driver, String url, String username, String password) throws ClassNotFoundException, SQLException {
Class.forName(driver);
if ((username == null) || (password == null) || (username.trim().length() == 0) || (password.trim().length() == 0)) {
return DriverManager.getConnection(url);
} else {
return DriverManager.getConnection(url, username, password);
}
}
public static void close(Connection connection) {
try {
if (connection != null) {
connection.close();
}
} catch (SQLException e) {
e.printStackTrace();
}
}
public static void close(Statement st) {
try {
if (st != null) {
st.close();
}
} catch (SQLException e) {
e.printStackTrace();
}
}
public static void close(ResultSet rs) {
try {
if (rs != null) {
rs.close();
}
} catch (SQLException e) {
e.printStackTrace();
}
}
public static void rollback(Connection connection) {
try {
if (connection != null) {
connection.rollback();
}
} catch (SQLException e) {
e.printStackTrace();
}
}
public static List<Map<String, Object>> map(ResultSet rs) throws SQLException {
List<Map<String, Object>> results = new ArrayList<Map<String, Object>>();
try {
if (rs != null) {
ResultSetMetaData meta = rs.getMetaData();
int numColumns = meta.getColumnCount();
while (rs.next()) {
Map<String, Object> row = new HashMap<String, Object>();
for (int i = 1; i <= numColumns; ++i) {
String name = meta.getColumnName(i);
Object value = rs.getObject(i);
row.put(name, value);
}
results.add(row);
}
}
} finally {
close(rs);
}
return results;
}
public static List<Map<String, Object>> query(Connection connection, String sql, List<Object> parameters) throws SQLException {
List<Map<String, Object>> results = null;
PreparedStatement ps = null;
ResultSet rs = null;
try {
ps = connection.prepareStatement(sql);
int i = 0;
for (Object parameter : parameters) {
ps.setObject(++i, parameter);
}
rs = ps.executeQuery();
results = map(rs);
} finally {
close(rs);
close(ps);
}
return results;
}
public static int update(Connection connection, String sql, List<Object> parameters) throws SQLException {
int numRowsUpdated = 0;
PreparedStatement ps = null;
try {
ps = connection.prepareStatement(sql);
int i = 0;
for (Object parameter : parameters) {
ps.setObject(++i, parameter);
}
numRowsUpdated = ps.executeUpdate();
} finally {
close(ps);
}
return numRowsUpdated;
}
}

You can write helper functions that parse a ResultSet and convert it into an ArrayList or an array or even the fields of an object. For instance, lets say you have a table of orders and then a query returns all of the rows of that table for a particular user (customer). We could then do something like this:
static List<Order> parseOrder(ResultSet rs) {
ArrayList<Order> orderList = new ArrayList<>();
while(rs.next() ) {
Order order = new Order();
order.setID(rs.getInt(1));
order.setCustomerID(rs.getInt(2));
order.setItemName(rs.getString(3));
orderList.add(order);
}
return orderList;
}
Simply turning the result set into an array of an array of Objects would be more general, but probably less useful.
I would leave it up to the calling function to close this ResultSet and possible the PreparedStatement (or Statement) and database connection.

Postgres Exception : No results were returned by the query.

I am trying to insert some rows in to a table... I am using postgressql-7.2.jar.
I get the following exception
org.postgresql.util.PSQLException: No results were returned by the query.
at org.postgresql.jdbc2.AbstractJdbc2Statement.executeQuery(AbstractJdbc2Statement.java:255)
I have already Googled and the possible reasons suggested are
Use executeUpdate() method or execute() method instead of executeQuery() method.
This could possibly be because of jar problem; try other versions of postgres jars.
In some places they save it could be because of heap space error.
I have tried all the three solutions but none of them work...
I am not pasting the code since I have just used statement.executeUpdate(queryString).
The insert statements load the data in to the table but still I get this error.
Can some one help me out in this?

What type of SQL statement are you trying to run with executeQuery()? It should not be an INSERT or UPDATE - these are not queries.
Without posting the actual SQL statement, code samples, or what the table looks like - it's pretty hard to actually help you with your problem. Without specifics all we can do is guess.

This code works perfectly for me running PostgreSQL 8.1 and its driver. Perhaps it can be a template for finding what's wrong with yours.
You need a single table named PERSON with columns PERSON_ID, FIRST_NAME, LAST_NAME. I made PERSON_ID the auto incremented primary key.
package persistence;
import java.sql.*;
import java.util.*;
public class DatabaseUtils
{
private static final String DEFAULT_DRIVER = "org.postgresql.Driver";
private static final String DEFAULT_URL = "jdbc:postgresql://localhost:5432/party";
private static final String DEFAULT_USERNAME = "pgsuper";
private static final String DEFAULT_PASSWORD = "pgsuper";
public static void main(String[] args)
{
String driver = ((args.length > 0) ? args[0] : DEFAULT_DRIVER);
String url = ((args.length > 1) ? args[1] : DEFAULT_URL);
String username = ((args.length > 2) ? args[2] : DEFAULT_USERNAME);
String password = ((args.length > 3) ? args[3] : DEFAULT_PASSWORD);
Connection connection = null;
try
{
connection = createConnection(driver, url, username, password);
DatabaseMetaData meta = connection.getMetaData();
System.out.println(meta.getDatabaseProductName());
System.out.println(meta.getDatabaseProductVersion());
String sqlQuery = "SELECT PERSON_ID, FIRST_NAME, LAST_NAME FROM PERSON ORDER BY LAST_NAME";
System.out.println("before insert: " + query(connection, sqlQuery, Collections.EMPTY_LIST));
connection.setAutoCommit(false);
String sqlUpdate = "INSERT INTO PERSON(FIRST_NAME, LAST_NAME) VALUES(?,?)";
List parameters = Arrays.asList( "Foo", "Bar" );
int numRowsUpdated = update(connection, sqlUpdate, parameters);
connection.commit();
System.out.println("# rows inserted: " + numRowsUpdated);
System.out.println("after insert: " + query(connection, sqlQuery, Collections.EMPTY_LIST));
}
catch (Exception e)
{
rollback(connection);
e.printStackTrace();
}
finally
{
close(connection);
}
}
public static Connection createConnection(String driver, String url, String username, String password) throws ClassNotFoundException, SQLException
{
Class.forName(driver);
if ((username == null) || (password == null) || (username.trim().length() == 0) || (password.trim().length() == 0))
{
return DriverManager.getConnection(url);
}
else
{
return DriverManager.getConnection(url, username, password);
}
}
public static void close(Connection connection)
{
try
{
if (connection != null)
{
connection.close();
}
}
catch (SQLException e)
{
e.printStackTrace();
}
}
public static void close(Statement st)
{
try
{
if (st != null)
{
st.close();
}
}
catch (SQLException e)
{
e.printStackTrace();
}
}
public static void close(ResultSet rs)
{
try
{
if (rs != null)
{
rs.close();
}
}
catch (SQLException e)
{
e.printStackTrace();
}
}
public static void rollback(Connection connection)
{
try
{
if (connection != null)
{
connection.rollback();
}
}
catch (SQLException e)
{
e.printStackTrace();
}
}
public static List<Map<String, Object>> map(ResultSet rs) throws SQLException
{
List<Map<String, Object>> results = new ArrayList<Map<String, Object>>();
try
{
if (rs != null)
{
ResultSetMetaData meta = rs.getMetaData();
int numColumns = meta.getColumnCount();
while (rs.next())
{
Map<String, Object> row = new HashMap<String, Object>();
for (int i = 1; i <= numColumns; ++i)
{
String name = meta.getColumnName(i);
Object value = rs.getObject(i);
row.put(name, value);
}
results.add(row);
}
}
}
finally
{
close(rs);
}
return results;
}
public static List<Map<String, Object>> query(Connection connection, String sql, List<Object> parameters) throws SQLException
{
List<Map<String, Object>> results = null;
PreparedStatement ps = null;
ResultSet rs = null;
try
{
ps = connection.prepareStatement(sql);
int i = 0;
for (Object parameter : parameters)
{
ps.setObject(++i, parameter);
}
rs = ps.executeQuery();
results = map(rs);
}
finally
{
close(rs);
close(ps);
}
return results;
}
public static int update(Connection connection, String sql, List<Object> parameters) throws SQLException
{
int numRowsUpdated = 0;
PreparedStatement ps = null;
try
{
ps = connection.prepareStatement(sql);
int i = 0;
for (Object parameter : parameters)
{
ps.setObject(++i, parameter);
}
numRowsUpdated = ps.executeUpdate();
}
finally
{
close(ps);
}
return numRowsUpdated;
}
}

A statement inserting rows does not return any rows back as a result, as opposed to a SELECT.