Develop Reference

How to get data from an ArrayList <List> in another class?

I'm using RecyclerView I have an Activity that queries my database and I insert this data into that ArrayList , and I want to list that data in another Activity.
This is where I query and add the data to the ArrayList
String queryProduto = "SELECT" +
" Produto_Servico.ID, Produto_Servico.Descricao," +
" Produto_Estoque.EstoqueAtual, ValorVenda" +
" FROM" +
" Produto_Valor" +
" INNER JOIN" +
" Produto_Servico" +
" ON" +
" Produto_Servico.ID = Produto_Valor.ID_Produto" +
" INNER JOIN" +
" Produto_Estoque" +
" ON" +
" Produto_Estoque.ID_Produto = Produto_Servico.ID" +
" WHERE" +
" Produto_Estoque.EstoqueAtual > 0" +
" ORDER BY" +
" Produto_Servico.Descricao";
Statement stmtP = connect.createStatement();
ResultSet rsP = stmtP.executeQuery(queryProduto);
String queryPessoa = "SELECT ID_Pessoa FROM Novo_Pedido";
Statement stmtPS = connect.createStatement();
ResultSet rsPS = stmtPS.executeQuery(queryPessoa);
while (rsPS.next()){
cod = rsPS.getString("ID_Pessoa");
}
if (rsP != null) {
while (rsP.next()) {
id = String.valueOf(rsP.getString("ID"));
desc = rsP.getString("Descricao");
estoque = String.valueOf(rsP.getString("EstoqueAtual"));
valorDec = rsP.getBigDecimal(4);
qtdStr = String.valueOf(qtd);
valorStr = decimalFormat.format(valorDec);
String descFinal = desc;
String qtdFinal = qtdStr;
final BigDecimal[] valorFinal = {valorDec};
try {
listProdutosPedidosFinalizar.add(new ListProdutosPedidosFinalizar(descFinal, qtdFinal, valorFinal[0], BigDecimal.ZERO));
classeLists.setListProdutosPedidosFinalizar(listProdutosPedidosFinalizar);
produtosPedidosAdapter = new ProdutosPedidosAdapter(listProdutosPedidos, this, new ProdutosPedidosAdapter.OnClickListener() {
/*METHODS*/
produtosPedidosAdapter.notifyDataSetChanged();
listProdutosPedidos.add(new ListProdutosPedidos(id, desc, estoque, valorStr, qtdStr));
} catch (Exception ex) {
ex.printStackTrace();
}
rvProdutosPedidos.setAdapter(produtosPedidosAdapter);
produtosPedidosAdapter.notifyDataSetChanged();
isSuccess = true;
}
And now I want to list the listProdutosPedidos data in another Activity.

Define listProdutosPedidos list as static member of your class and then use className.listProdutosPedidos code to access records in it.

Pass value of an object from DAO to servlet in 2D array

I would like to print the values of an object from DAO to servlet.
DAO:
public static List getFree(String svLectID,String ExLectID) throws SQLException, ClassNotFoundException
{
currentCon = JavaConnectionDB.getConnection() ;
PreparedStatement ps1 = currentCon.prepareStatement("SELECT *\n" +
"FROM (\n" +
" SELECT e1.FreeID,\n" +
" e1.lecturerID SVID,\n" +
" e1.availableID SVavail,\n" +
" e1.freedate AS SVFree,\n" +
" e2.lecturerID AS Examiner, \n" +
" e2.freedate EXFree,\n" +
" s.studentID,\n" +
" s.studentName,\n" +
" s.lecturerID AS lectID,\n" +
" sv.lecturerID AS SVlecturerID,\n" +
" sv.lecturerFullname AS SVlecturerName,\n" +
" ex.lecturerID AS EXlecturerID,\n" +
" ex.lecturerFullname AS EXlecturerName,\n" +
" v.availableID availID,\n" +
" v.availableDay,\n" +
" v.availableStart,\n" +
" v.availableEnd,\n" +
" ROW_NUMBER() OVER (PARTITION BY e1.lecturerID \n" +
" ORDER BY dbms_random.random) AS rn\n" +
" FROM free e1 \n" +
" INNER JOIN free e2 \n" +
" ON e1.availableID = e2.availableID\n" +
" INNER JOIN student s\n" +
" ON s.lecturerID = e1.lecturerID\n" +
" INNER JOIN lecturer sv\n" +
" ON sv.lecturerID = e1.lecturerID\n" +
" INNER JOIN lecturer ex\n" +
" ON ex.lecturerID = e2.lecturerID\n" +
" INNER JOIN availability v\n" +
" ON v.availableID = e2.availableID\n" +
" \n" +
" \n" +
" WHERE e1.lecturerID = ? \n" +
" AND e2.lecturerID = ? \n" +
" ORDER BY e2.availableID asc\n" +
" \n" +
" )\n" +
"WHERE rn <=5") ;
ps1.setString(1, svLectID) ;
ps1.setString(2, ExLectID);
List list = new ArrayList() ;
ResultSet rs1 = ps1.executeQuery() ;
while(rs1.next())
{
Object[] obj = new Object[17] ;
obj[0] = rs1.getString(1) ;
obj[1] = rs1.getString(2);
obj[2] = rs1.getInt(3);
obj[3] = rs1.getDate(4);
obj[4] = rs1.getString(5);
obj[5] = rs1.getDate(6);
obj[6] = rs1.getString(7);
obj[7] = rs1.getString(8);
obj[8] = rs1.getString(9);
obj[9] = rs1.getString(10);
obj[10] = rs1.getString(11);
obj[11] = rs1.getString(12);
obj[12] = rs1.getString(13);
obj[13] = rs1.getInt(14);
obj[14] = rs1.getString(15);
obj[15] = rs1.getDate(16);
obj[16] = rs1.getDate(17);
list.add(obj) ;
System.out.println("zabir "+rs1.getString(8));
}
return list ;
}
As you can see these values are stored in an object into a list. I retrieve these values to servlet.
SERVLET:
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, java.io.IOException {
currentCon = JavaConnectionDB.getConnection();
// Set response content type
response.setContentType("text/html");
PrintWriter out = response.getWriter();
ServletContext context=getServletContext();
String[] studentID = request.getParameterValues("studentID");
String[] supervisorID = request.getParameterValues("supervisorID");
String[] examinerID = request.getParameterValues("examinerID");
DateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyy-MM-dd");
try{
out.println("<br><center><table><tr>"
+ "<th>Student Name</th>"
+ "<th>Project Title</th>"
+ "<th>Supervisor Name</th>"
+ "<th>Examiner Name</th>"
+ "<th>Start</th>"
+ "<th>End</th>"
+ "<th>Date</th>"
+ "</tr>");
for (int i=0 ; i<studentID.length ; i++){
FreeBean free = new FreeBean();
PresentationBean present = new PresentationBean();
StudentBean student = new StudentBean();
List list = new ArrayList() ;
int SVavailableID = free.getAvailableID();
int EXavailableID = free.getAvailableID();
list = GenerateScheduleDAO.getFree(supervisorID[i],examinerID[i]);
System.out.println(list.get(0)); //DEBUGGED HERE
System.out.println(list); //DEBUGGED HERE
out.println("<tr>");
out.println("<tr>");
out.println("<td>"+ studentID[i]+"</td>");
out.println("<td> Hello </td>");
out.println("<td>"+ supervisorID[i] +"</td>");
out.println("<td>"+ examinerID[i] +"</td>");
out.println("<td>"+ SVavailableID+"</td>");
out.println("<td>"+ EXavailableID+"</td>");
out.println("<td>"+ EXFreeDate+"</td>");
out.println("</tr>");
}//student loop
out.println("</center></table><br><br>");
out.println("</body>");
out.println("</html>");
}// first try
catch (Exception e)
{
e.printStackTrace() ;
}//first catch
}//throws method
I tried to get the value using SOP first like this:
System.out.println(list.get(0)); //DEBUGGED HERE
System.out.println(list); //DEBUGGED HERE
First SOP produce : [Ljava.lang.Object;#13432ad
Second SOP produce : [[Ljava.lang.Object;#1dd079f,
My first assumption was get(0) wil give me FreeID value. As declared in DAO.
So how can i get the value if using get(0) is wrong?

Your freeId should be in the first position of each array present in the list returned by the method getFree.
To get the freeId of the first element of the list you should do something like:
System.out.println((Object[]) list.get(0))[0]);
For the freeId of the second element of the list:
System.out.println((Object[]) list.get(1))[0]);
and so on.
It will be more readable doing something like that:
Object[] firstObjectAsArray = (Object[]) list.get(0);
System.out.println(firstObjectAsArray[0]);
Object[] secondObjectAsArray = (Object[]) list.get(1);
System.out.println(secondObjectAsArray[0]);
To print the freeId of all elements of the list
for (Object objectAsArray : list) {
System.out.println(((Object[]) objectAsArray)[0]);
}
Note: looking at your code there is a not necessary creation of an empty list. The code:
List list = new ArrayList() ; // Not necessary
int SVavailableID = free.getAvailableID();
int EXavailableID = free.getAvailableID();
list = GenerateScheduleDAO.getFree(supervisorID[i],examinerID[i]);
can be optimized as follow:
int SVavailableID = free.getAvailableID();
int EXavailableID = free.getAvailableID();
List list = GenerateScheduleDAO.getFree(supervisorID[i],examinerID[i]);
Note: using generics you don't need the cast. To do that replace the definition of the list
List list = new ArrayList();
with
List<Object[]> list = new ArrayList<Object[]>();

Your list contains arrays of Object, so you have to call the relevant indexes of the array.
You could debug the full list like this
// iterate over the list
for (int i = 0; i < list.size(); i++) {
Object[] array = (Object[])(list.get(i));
// iterate over the Object array
for (int j = 0; j < array.length; j++) {
System.out.println(array[j]);
}
}

return array from inside an if,for statement

I am building a tag reader for inventory purpose. Using the for loop to iterate through the tags to count/total the ids. I get an error on my return line "tagsFound cannot be resolved into a variable". How do i use the variable inside the for loop and then access it outside the loop?
public String[] getTags(AlienClass1Reader reader)throws AlienReaderException{
int coneCount = 0;
int drumCount = 0;
// Open a connection to the reader
reader.open();
// Ask the reader to read tags and print them
Tag tagList[] = reader.getTagList();
if (tagList == null) {
System.out.println("No Tags Found");
} else {
System.out.println("Tag(s) found: " + tagList.length);
for (int i=0; i<tagList.length; i++) {
Tag tag = tagList[i];
System.out.println("ID:" + tag.getTagID() +
", Discovered:" + tag.getDiscoverTime() +
", Last Seen:" + tag.getRenewTime() +
", Antenna:" + tag.getAntenna() +
", Reads:" + tag.getRenewCount()
);
//tagFound[i]= "" + tag.getTagID();
String phrase = tag.getTagID();
tagFound[i] = phrase;
String delims = "[ ]+";
String[] tokens = phrase.split(delims);
if (tokens[0].equals("0CCE") && tokens[3].equals("1001")){drumCount++;}
if (tokens[0].equals("0CCE") && tokens[3].equals("1004")){coneCount++;}
String[] tagsFound;
tagsFound[i] = tag.getTagID();
}
System.out.println("Cones= " + coneCount);
System.out.println("Drums= " + drumCount);
// Close the connection
reader.close();
return tagsFound;
}
}

public String[] getTags(AlienClass1Reader reader)throws AlienReaderException{
int coneCount = 0;
int drumCount = 0;
// Open a connection to the reader
reader.open();
// Ask the reader to read tags and print them
Tag tagList[] = reader.getTagList();
if (tagList == null) {
System.out.println("No Tags Found");
} else {
System.out.println("Tag(s) found: " + tagList.length);
String[] tagsFound = new String[tagList.length];
for (int i=0; i<tagList.length; i++) {
tagsFound = "";
Tag tag = tagList[i];
System.out.println("ID:" + tag.getTagID() +
", Discovered:" + tag.getDiscoverTime() +
", Last Seen:" + tag.getRenewTime() +
", Antenna:" + tag.getAntenna() +
", Reads:" + tag.getRenewCount()
);
//tagFound[i]= "" + tag.getTagID();
String phrase = tag.getTagID();
tagFound[i] = phrase;
String delims = "[ ]+";
String[] tokens = phrase.split(delims);
if (tokens[0].equals("0CCE") && tokens[3].equals("1001")){drumCount++;}
if (tokens[0].equals("0CCE") && tokens[3].equals("1004")){coneCount++;}
tagsFound[i] = tag.getTagID();
}
System.out.println("Cones= " + coneCount);
System.out.println("Drums= " + drumCount);
// Close the connection
reader.close();
return tagsFound;
}
}
the returned array will have empty strings in the positions where the tag does not satisfy the criteria.

importing data from csv file into access database using java

I need to import csv into access database using java. I tried using the following code
my code:
public static void main (String args[])
{
String dbFileSpec = "C:\\Documents and Settings\\admin\\My Documents\\NetBeansProjects\\AutomateExcelDatabase\\Centre.accdb";
// String accessTableName = "Centre";
String csvDirPath = "C:\\Documents and Settings\\admin\\My Documents\\NetBeansProjects\\AutomateExcelDatabase";
String csvFileName = "myjdbcfile.csv";
try (Connection conn = DriverManager.getConnection(
"jdbc:ucanaccess://" + dbFileSpec
// + ";newdatabaseversion=V2007"
)) {
try
{
String strSQL = "SELECT * INTO " + dbFileSpec + " FROM [Text;HDR=YES;DATABASE=" + csvDirPath + ";].[" + csvFileName + "]";
System.err.println("SQL --> "+strSQL);
PreparedStatement selectPrepSt = conn.prepareStatement(strSQL);
boolean result = selectPrepSt.execute();
System.out.println("result = " + result);
}
catch(SQLException ex)
{
System.err.println("Error --->"+ex.toString());
}
conn.commit();
conn.close();
} catch (SQLException ex) {
Logger.getLogger(NewClass.class.getName()).log(Level.SEVERE, null, ex);
}
}
}
But it throws error as "net.ucanaccess.jdbc.UcanaccessSQLException: unexpected token: INTO required: FROM".

The two problems with trying to use
SELECT ... INTO NewTableName FROM [Text; ...].[csvFileName]
in this context are:
SELECT ... INTO NewTableName FROM OldTableName is an Access SQL construct that UCanAccess does not support (at least not at the moment), and
... FROM [Text; ...].[csvFileName] is an ODBC "trick" and UCanAccess does not use ODBC.
However, UCanAccess uses HSQLDB and HSQLDB offers support for reading CSV files like so:
final String csvFolder = "C:/__tmp/zzzTest/";
final String csvFileName = "myjdbcfile.csv";
final String csvDbName = "hsqldbTemp";
try (Connection hconn = DriverManager.getConnection(
"jdbc:hsqldb:file:" + csvFolder + "/" + csvDbName,
"SA",
"")) {
try (Statement s = hconn.createStatement()) {
s.executeUpdate("CREATE TEXT TABLE fromcsv (id int, textcol varchar(50))");
s.executeUpdate("SET TABLE fromcsv SOURCE \"" + csvFileName + "\" DESC");
try (ResultSet rs = s.executeQuery("SELECT * FROM fromcsv")) {
while (rs.next()) {
System.out.println(rs.getString("textcol"));
}
}
s.executeUpdate("SHUTDOWN");
File f = null;
f = new File(csvFolder + "/" + csvDbName + ".properties");
f.delete();
f = new File(csvFolder + "/" + csvDbName + ".script");
f.delete();
}
} catch (Exception e) {
e.printStackTrace(System.out);
}
so you could use two connections,
one jdbc:ucanaccess connection to the Access database, and
another jdbc:hsqldb connection to the CSV file,
and then insert the rows from the CSV file into a table in the Access database.

You have mis-typed the query here,
String strSQL = "SELECT * INTO " + dbFileSpec + " FROM
[Text;HDR=YES;DATABASE=" + csvDirPath + ";].[" + csvFileName + "]";
should be ,
String strSQL = "SELECT *" + dbFileSpec + " FROM [Text;HDR=YES;DATABASE=" + csvDirPath + ";].[" + csvFileName + "]";

Hashmap not populating

I'm trying to populate Hashmap as following:
public static final String KEY_PROPNAME = "";
public static final String KEY_KEYWORDS = "";
public static final String KEY_THUMB_URI = "";
ArrayList<HashMap<String, String>> clipsList = new ArrayList<HashMap<String, String>>();
for (int i = 0; i < clipDetailsArr.length; i = i
+ constants.noOfColumns) {
HashMap<String, String> map = new HashMap<String, String>();
map.put(KEY_PROPNAME, clipDetailsArr[i]);
map.put(KEY_PROPTYPE, clipDetailsArr[i + 1]);
map.put(KEY_PRICE, clipDetailsArr[i + 2]);
map.put(KEY_LOCATION, clipDetailsArr[i + 3]);
map.put(KEY_SQFT, clipDetailsArr[i + 4]);
map.put(KEY_SQFTTYPE, clipDetailsArr[i + 5]);
map.put(KEY_BED, clipDetailsArr[i + 6]);
map.put(KEY_BATH, clipDetailsArr[i + 7]);
map.put(KEY_KEYWORDS, clipDetailsArr[i + 8]);
map.put(KEY_THUMB_URI, clipDetailsArr[i + 9]);
Log.i("Main", "Clip clipDetailsArr[]: 0=" + clipDetailsArr[i] + " ,1=" + clipDetailsArr[i + 1]
+ " ,2=" + clipDetailsArr[i + 2] + " ,3=" + clipDetailsArr[i + 3] + " ,4="
+ clipDetailsArr[i + 4] + " ,5=" + clipDetailsArr[i + 5] + " ,6="
+ clipDetailsArr[i + 6] + " ,7=" + clipDetailsArr[i + 7] + " ,8="
+ clipDetailsArr[i + 8] + " ,9=" + clipDetailsArr[i + 9]);
Log.i("Main", "Clip PROPNAME=" + MainActivity.KEY_PROPNAME
+ " ,KEYWORDS" + MainActivity.KEY_KEYWORDS + " ,URI="
+ MainActivity.KEY_THUMB_URI);
Log.i("Main", "Clip get PROPNAME=" + map.get(KEY_PROPNAME)
+ " ,KEYWORDS" + map.get(KEY_KEYWORDS) + " ,URI="
+ map.get(KEY_THUMB_URI));
clipsList.add(map);
}
Output of log is something like this:
Clip clipDetailsArr[]: 0=Opt out ,1=Residentail ,2=10000 ,3=Andheri ,4=500 ,5=Carpet ,6=2 ,7=1 ,8=optout ,9=/mnt/sdcard/Clipping/optout.png
Clip PROPNAME= ,KEYWORDS ,URI=
Clip get PROPNAME=/mnt/sdcard/Clipping/optout.png,
KEYWORDS/mnt/sdcard/Clipping/optout.png,
URI=/mnt/sdcard/Clipping/optout.png//AND SO ON
Referring to above log, I have values in my array and I'm putting them into array by using map.put(key,value) but in 2nd log MainActivity.KEY_PROPNAME and other fields are empty. Also, when I use map.get(key), all the column have data of last column.
Note that last column data is getting populated appropriately.
Am I doing something wrong here? Any help appreciated.

You are using the same key "" for at least three .put() !! You have defined :
public static final String KEY_PROPNAME = "";
public static final String KEY_KEYWORDS = "";
public static final String KEY_THUMB_URI = "";
And then you populate the Map as :
map.put(KEY_PROPNAME, clipDetailsArr[i]);
map.put(KEY_KEYWORDS, clipDetailsArr[i + 8]);
map.put(KEY_THUMB_URI, clipDetailsArr[i + 9]);
As per the Javadoc:
If the map previously contained a mapping for the key, the old value is replaced.

public static final String KEY_PROPNAME = "";
public static final String KEY_KEYWORDS = "";
public static final String KEY_THUMB_URI = "";
Here all of your keys have same value/name, Hence all the data will store in the same key !!

public static final String KEY_PROPNAME = "";
public static final String KEY_KEYWORDS = "";
public static final String KEY_THUMB_URI = "";
This is the error, instead of creating empty strings from your name you should use them as the Keys to get your requested behavior.
Just to keep your code almost the same you could to something like:
public static final String KEY_PROPNAME = "KEY_PROPNAME";
public static final String KEY_KEYWORDS = "KEY_KEYWORDS";
public static final String KEY_THUMB_URI = "KEY_THUMB_URI";
That should to the trick even if it is a little funky ;)