Develop Reference

Parsing csv line to Java objects

I was wondering if someone here could help me, I can't find a solution for my problem and I have tried everything.
What I am trying to do is read and parse lines in a csv file into java objects and I have succeeded in doing that but after it reads all the lines it should insert the lines into the database but it only inserts the 1st line the entire time and I don't no why. When I do a print it shows that it is reading all the lines and placing them in the objects but as soon as I do the insert it wants to insert only the 1st line.
Please see my code below:
public boolean lineReader(File file){
BufferedReader br = null;
String line= "";
String splitBy = ",";
storeList = new ArrayList<StoreFile>();
try {
br = new BufferedReader(new FileReader(file));
while((line = br.readLine())!=null){
line = line.replace('|', ',');
//split on pipe ( | )
String[] array = line.split(splitBy, 14);
//Add values from csv to store object
//Add values from csv to storeF objects
StoreFile StoreF = new StoreFile();
if (array[0].equals("H") || array[0].equals("T")) {
return false;
} else {
StoreF.setRetailID(array[1].replaceAll("/", ""));
StoreF.setChain(array[2].replaceAll("/",""));
StoreF.setStoreID(array[3].replaceAll("/", ""));
StoreF.setStoreName(array[4].replaceAll("/", ""));
StoreF.setAddress1(array[5].replaceAll("/", ""));
StoreF.setAddress2(array[6].replaceAll("/", ""));
StoreF.setAddress3(array[7].replaceAll("/", ""));
StoreF.setProvince(array[8].replaceAll("/", ""));
StoreF.setAddress4(array[9].replaceAll("/", ""));
StoreF.setCountry(array[10].replaceAll("/", ""));
StoreF.setCurrency(array[11].replaceAll("/", ""));
StoreF.setAddress5(array[12].replaceAll("/", ""));
StoreF.setTelNo(array[13].replaceAll("/", ""));
//Add stores to list
storeList.add(StoreF);
}
} //print list stores in file
printStoreList(storeList);
executeStoredPro(storeList);
} catch (Exception ex) {
nmtbatchservice.NMTBatchService2.LOG.error("An exception accoured: " + ex.getMessage(), ex);
//copy to error folder
//email
}
return false;
}
public void printStoreList(List<StoreFile> storeListToPrint) {
for(int i = 0; i <storeListToPrint.size();i++){
System.out.println( storeListToPrint.get(i).getRetailID()
+ storeListToPrint.get(i).getChain()
+ storeListToPrint.get(i).getStoreID()
+ storeListToPrint.get(i).getStoreName()
+ storeListToPrint.get(i).getAddress1()
+ storeListToPrint.get(i).getAddress2()
+ storeListToPrint.get(i).getAddress3()
+ storeListToPrint.get(i).getProvince()
+ storeListToPrint.get(i).getAddress4()
+ storeListToPrint.get(i).getCountry()
+ storeListToPrint.get(i).getCurrency()
+ storeListToPrint.get(i).getAddress5()
+ storeListToPrint.get(i).getTelNo());
}
}
public void unzip(String source, String destination) {
try {
ZipFile zipFile = new ZipFile(source);
zipFile.extractAll(destination);
deleteStoreFile(source);
} catch (ZipException ex) {
nmtbatchservice.NMTBatchService2.LOG.error("Error unzipping file : " + ex.getMessage(), ex);
}
}
public void deleteStoreFile(String directory) {
try {
File file = new File(directory);
file.delete();
} catch (Exception ex) {
nmtbatchservice.NMTBatchService2.LOG.error("An exception accoured when trying to delete file " + directory + " : " + ex.getMessage(), ex);
}
}
public void executeStoredPro(List<StoreFile> storeListToInsert) {
Connection con = null;
CallableStatement st = null;
try {
String connectionURL = MSSQLConnectionURL;
Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver").newInstance();
con = DriverManager.getConnection(connectionURL, MSSQLUsername, MSSQLPassword);
for(int i = 0; i <storeListToInsert.size();i++){
st = con.prepareCall( "IF EXISTS (SELECT * FROM tblPay#RetailStores WHERE StoreID = " + storeListToInsert.get(i).getStoreID() + " AND RetailID = "+ storeListToInsert.get(i).getRetailID() + ")"
+ " UPDATE tblPay#RetailStores "
+ " SET RetailID = '" + storeListToInsert.get(i).getRetailID() + "',"
+ " StoreID = '" + storeListToInsert.get(i).getStoreID() + "',"
+ " StoreName = '" + storeListToInsert.get(i).getStoreName() + "',"
+ " TestStore = 0,"
+ " Address1 = '" + storeListToInsert.get(i).getAddress1() + "',"
+ " Address2 = '" + storeListToInsert.get(i).getAddress2() + "',"
+ " Address3 = '" + storeListToInsert.get(i).getAddress3() + "',"
+ " Address4 = '" + storeListToInsert.get(i).getAddress4() + "',"
+ " Address5 = '" + storeListToInsert.get(i).getAddress5() + "',"
+ " Province = '" + storeListToInsert.get(i).getProvince() + "',"
+ " TelNo = '" + storeListToInsert.get(i).getTelNo() + "',"
+ " Enabled = 1"
+ " ELSE "
+ " INSERT INTO tblPay#RetailStores ( [RetailID], [StoreID], [StoreName], [TestStore], [Address1], [Address2], [Address3], [Address4], [Address5], [Province], [TelNo] , [Enabled] ) "
+ " VALUES "
+ "('" + storeListToInsert.get(i).getRetailID() + "',"
+ "'" + storeListToInsert.get(i).getStoreID() + "',"
+ "'" + storeListToInsert.get(i).getStoreName() + "',"
+ "0,"
+ "'" + storeListToInsert.get(i).getAddress1() + "',"
+ "'" + storeListToInsert.get(i).getAddress2() + "',"
+ "'" + storeListToInsert.get(i).getAddress3() + "',"
+ "'" + storeListToInsert.get(i).getAddress4() + "',"
+ "'" + storeListToInsert.get(i).getAddress5() + "',"
+ "'" + storeListToInsert.get(i).getProvince() + "',"
+ "'" + storeListToInsert.get(i).getTelNo() + "',"
+ "1)");
st.executeUpdate();
}
con.close();
} catch (Exception ex) {
nmtbatchservice.NMTBatchService2.LOG.error("Error executing Stored proc with error : " + ex.getMessage(), ex);
nmtbatchservice.NMTBatchService2.mailingQueue.addToQueue(new Mail("support#nmt-it.co.za", "Service Email Error", "An error occurred during Store Import failed with error : " + ex.getMessage()));
}
}
Any advise would be appreciated.
Thanks

Formatting aside, your code is wrong (I truncated the part of the query):
for(int i = 0; i <storeListToInsert.size();i++){
st = con.prepareCall( "IF EXISTS (SELECT * FROM tblPay#RetailStores ...
+ "'" + storeListToInsert.get(i).getTelNo() + "',"
+ "1)");
st.executeUpdate();
}
Don't do a classical for loop while foreach exists and can be better to use, and even if you do a classical for loop, use local variables, eg:
for(int i = 0; i <storeListToInsert.size();i++){
StoreFile item = storeListToInsert.get(i);
st = con.prepareCall( "IF EXISTS (SELECT * FROM tblPay#RetailStores ...
+ "'" + item.getTelNo() + "',"
+ "1)");
st.executeUpdate();
}
Which could translate as:
for (StoreFile item : storeListToInsert) {
st = con.prepareCall( "IF EXISTS (SELECT * FROM tblPay#RetailStores ...
+ "'" + item.getTelNo() + "',"
+ "1)");
st.executeUpdate();
}
Now, the second problem is your PreparedStatement. A PreparedStatement allow reusing, which means you don't need to create PreparedStatement per item which is what you are doing.
Also, you need to close the statement otherwise, you will exhaust resources..
You must not create it in the for loop, but before, like this:
PreparedStatement st = null;
try {
st = con.prepareCall( "IF EXISTS (SELECT * FROM tblPay#RetailStores ...
+ "SET RetailID = :RetailID ,"
+ "1)");
for (StoreFile item : storeListToInsert) {
st.setString(":RetailID", item.getRetailID());
st.executeUpdate();
}
} finally {
if (null != st) {st.close();}
}
In brief:
You need to close the PreparedStatement after usage, because it is a memory leak otherwise.
You need to rewrite your query using either named parameters, either positional parameter (like: ? or ?1 for first parameter, and so on). I favor named parameters, but they are not always available. The example I linked all use positional parameters.
You need to set the value for each parameters in the for loop, and care about the type. I expected here that getRetailID() is a String, but it might be a Long in that case that would be st.setLong.
Your query is reusable, avoiding the need to reparse it/resend it to the SQL Server. You just send the parameter's values. Beside, you can also batch update.
A PreparedStatement for a statement that you generate (like you are doing) is overkill, and beside, it is missing SQL escapement to protect the String you inject to your query to avoid it being badly interpreted (aka SQL errors) or worst, to do what it was not intended for (like, even if it is far fetched, dropping the whole database, etc).
The executeUpdate() return the number of updated rows. You can check it to see if there was updates.
You can also use Batch statement, which can help performances.
And finally, you can use opencsv to parse common CSV files.

Adding several columns in update query

Im trying to update several columns in a row through a dynamic query.
columnnames is an Arraylist containing all the names of the columns for the selected table
Arrays.toString(row) contains the user inputs that the row should be updated to.
Im getting this error message at columnnames when trying to run this: No such column[SNO,SNAME,STATUS,CITY]. I dont know of any way to fix this?
query = "UPDATE " + tablename + " SET '" + columnnames + "' = '" + Arrays.toString(row) + "' WHERE " + FirstColumn + " = '" + rowstandard + "'";

You need to update each column separately. You can't pass them each as arrays.
query = "UPDATE " + tablename + " SET "
foreach(int i=0; i< columnnames.length; i++)
{
query+= "'" + columnnames[i] + "' = '" + row[i] + "',"
}
query = StripLastComma(query) //Not sure how to do this in Java.
query +="' WHERE " + FirstColumn + " = '" + rowstandard + "'"

Thats not going to work as the syntax for set is SET ColumnA = :ValueA, ColumnB = :ValueB WHERE " + FirstColumn + " = '" + rowstandard + "'";

As it was pointed out correct syntax for update query is:
UPDATE [LOW_PRIORITY] [IGNORE] table_reference
SET col_name1={expr1|DEFAULT} [, col_name2={expr2|DEFAULT}] ...
[WHERE where_condition]
[ORDER BY ...]
[LIMIT row_count]
see Update syntax.
Having said that, I would do something like this (using guava):
StringBuilder query = new StringBuilder();
query.append("UPDATE " + tablename + " SET ");
// build a map of col name/value
Map<String, String> map = Maps.toMap(columnnames, new Function<String, String>(){
#Override
public String apply(String input){
return row[columnnames.indexOf(input)].toString();
}
});
query.append(Joiner.on(",").withKeyValueSeparator("=").join(map));
query.append(" WHERE " + FirstColumn + " = '" + rowstandard + "'");
query.toString();

Sql update query with Single quotes

I am using hibernate application in java to retrieve and update database.
During updating a table,i forming an sql query as follows,
String qry = "UPDATE " + entity + " SET " + htmlColumn + " ='"+value+"' WHERE " + id + " = " + primaryId;
where value is a html string which contains single quotes sometimes.
How to escape ignore/escape the single quotes and update the table successfully
Thanks

use PreparedStatement for this
String qry = "UPDATE " + entity +
" SET " + htmlColumn + " = ? " +
"WHERE " + id + " = ?";
PreparedStatement pstmt = con.prepareStatement(qry);
pstmt.setString(1, value);
pstmt.setInt(2, primaryId);
pstmt.executeUpdate();
PreparedStatement

Don't set values directly.
currentSession()
.createQuery("UPDATE " + entity + " SET " + htmlColumn +
" = :value WHERE " + id + " :id")
.setParameter("value", value).setParameter(":id",id).executeUpdate();

You can replace the single quote with a double single quote. value.replace("'","''"); but you will need to cater for more than just that because your value can easily allow for SQL Injection if it is not properly catered for.

You can use preparedstatement as :
String query= "UPDATE " + entity + " SET " + htmlColumn + " =? WHERE " + id + " = " + primaryId;
PreparedStatement ptmt = con.prepareStatement(query);
ptmt.setString(1, value);

Insert query - executeUpdate returning -1

I am trying to insert records into SQL Server using jdbc conn (in java).
I am able to insert into SQL, if I manually copy the query statement in the java file. But its not inserting from the code?
Please help, where am I committing mistake?
PreparedStatement preparedStatement = null;
if (conn != null) {
System.out.println("Connection Successful!");
}
//Create a Statement object
Statement sql_stmt = conn.createStatement();
//Create a Statement object
Statement sql_stmt_1 = conn.createStatement();
//Result Set for Prouduct Table
ResultSet rs = sql_stmt.executeQuery("SELECT MAX(ID), MAX(RG_ID), MAX(WG_ID) FROM " + strDBName + ".[dbo].Product");
if ( rs.next() ) {
// Retrieve the auto generated key(s).
intID = rs.getInt(1);
intRG_ID = rs.getInt(2);
intWG_ID = rs.getInt(3);
}
for (int iCount = 0 ;iCount < arrListLevel_1_Unique.size(); iCount++)
{
//Result Set for Prouduct Table
sql_stmt_1.executeUpdate("\n IF NOT EXISTS(SELECT 1 FROM " + strDBName + ".[dbo].Product WHERE [Name] NOT LIKE '" + arrListLevel_1_Unique.get(iCount) + "') "
+ "\nINSERT INTO " + strDBName + ".[dbo].Product ([Name] ,"
+ "[RG_ID],[WG_ID],[Parent_Product]) "
+ "VALUES ( '" + arrListLevel_1_Unique.get(iCount) + "',"
+ + (intWG_ID + intRowIncrement) + ", " + (intWG_ID + intRowIncrement + 1) + ", 5828)");
intRowIncrement++ ;
}
rs.close();
sql_stmt.close();
sql_stmt_1.close();
//Close the database connection
conn.close();

You have two plus signs + in the fifth row:
+ + (intWG_ID + intRowIncrement) + ...
Otherwise, the problem may lie in the IF ... statement. You can try this instead:
sql_stmt_1.executeUpdate(
" INSERT INTO " + strDBName + ".[dbo].Product ([Name] ,"
+ "[RG_ID],[WG_ID],[Parent_Product]) "
+ " SELECT '" + arrListLevel_1_Unique.get(iCount) + "',"
+ (intWG_ID + intRowIncrement) + ", "
+ (intWG_ID + intRowIncrement + 1) + ", 5828 "
+ " WHERE NOT EXISTS( SELECT 1 FROM " + strDBName
+ ".[dbo].Product WHERE [Name] LIKE '"
+ arrListLevel_1_Unique.get(iCount) + "') "
) ;

I think the problem lies on the "\n", have you tried eliminating those 2 of "\n" and see if it's working?
Actually this kind of implementation (building SQL string with string concatenation) is really bad. At first is prone to SQL injection, and then secondly you will have problem if the value to be inserted contains character single quote or ampersand.
Instead, you should use "prepare statement".
And it's tidier to store the SQL string into a variable before executing it. So that you can log it (for debug purpose), roughly something like this:
String sqlCommand = "select * from " + tableName;
System.out.println(sqlCommand);
sqlStatement.executeUpdate(sqlCommand);
P.S. it is not advised to use system.out.println for debug, you should implement a proper logging system.

Why are my query results displaying differently when debugging?

This is strange... I'm displaying results in an HTML table but I'm getting a different number of results being displayed depending on if/how I am debugging. If I debug slowly and hit each line then all of the results show. If I just run it or don't step through each line then I only get one result in the table. Either way the result set does have the correct number of rows, they just aren't being displayed in the table correctly.
Does anyone have any ideas why this strange behavior is happening? I'm using Eclipse Indigo. Below is the block of code that I'm using to select the records and display them.
try {
String query =
"Select * from plants where name = '"
+ name + "'";
String plantName = "";
ResultSet rs = sttmnt.executeQuery(query);
while (rs.next()) { // display information for each plant.
plantName = rs.getString(2); // display fields in cells
out.println("<tr><td>");
out.println(plantName + "</td><td>");
out.println(rs.getString(3) + "</td><td>");
out.println("$" + rs.getString(5) + "</td><td>");
out.println(rs.getString(4) + "</td>");
out.println("<input type=\"hidden\" name=\"plantName" +
plantNo + "\" value=\"" + plantName + "\">");
out.println("<input type=\"hidden\" name=\"plantID" +
plantNo + "\" value=\"" + rs.getString(1) + "\">");
out.println("</tr>");
plantNo++;
}
if (plantNo == 0) out.println("<tr><td align=\"center\" " +
" colspan=\"4\">Sorry, there are currently no " + name
+ " plants for sale.</td></tr>");
else
out.println("<tr><td align=\"center\" " +
" colspan=\"4\">Showing " + plantNo
+ " results. </td></tr>");
out.println("</table>");
rs.close();
}

Try appending all the output to a StringBuffer and print that all out in one fell swoop. You'll save on objects, too. Your code becomes:
try {
String query = "Select * from plants where name = ?";
sttmnt.setString(1, name);
String plantName = "";
ResultSet rs = sttmnt.executeQuery(query);
StringBuffer output = new StringBuffer();
while (rs.next()) { // display information for each plant.
plantName = rs.getString(2); // display fields in cells
output.append("<tr><td>");
output.append(plantName + "</td><td>");
output.append(rs.getString(3) + "</td><td>");
output.append("$" + rs.getString(5) + "</td><td>");
output.append(rs.getString(4) + "</td>");
output.append("<input type=\"hidden\" name=\"plantName" +
plantNo + "\" value=\"" + plantName + "\">");
output.append("<input type=\"hidden\" name=\"plantID" +
plantNo + "\" value=\"" + rs.getString(1) + "\">");
output.append("</tr>");
plantNo++;
}
if (plantNo == 0) output.append("<tr><td align=\"center\" " +
" colspan=\"4\">Sorry, there are currently no " + name
+ " plants for sale.</td></tr>");
else
output.append("<tr><td align=\"center\" " +
" colspan=\"4\">Showing " + plantNo
+ " results. </td></tr>");
output.append("</table>");
out.println(output.toString());
rs.close();
}

Try putting an out.flush() at the end of your code. It's likely that the data is just sitting in a buffer waiting to be sent when you run the code normally.