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Operators in a table

There are 7 rows of output for table, how can I modify this so row 6 displays either of the three providers.
I tried something like this :
template.getProvider2() != null || template.getProvider3() != null ||
template.getProvider1() != null ?
template.getProvider2().getBusinessUnit(): "" ||
template.getProvider3().getBusinessUnit(): "" ||
template.getProvider3().getBusinessUnit(): "",
which gives me an error of StringBuilder not accepting the OR operator,
I'd appreciate any help on this.
Thanks
Here is my code:
public GetEmailTemplatesResponse getEmailTemplates() throws Exception {
StringBuilder stringBuilder = new StringBuilder();
String tableRow = "<tr><td>%s</td><td>%s</td><td>%s</td><td>%s</td><td>%s</td><td>%s</td><td>%s</td></tr>";
Map<String, EmailTemplate> templates = templateRedisCacheReader.getTemplatesByCacheType(CacheType.EMAIL_TEMPLATE);
templates.values()
.forEach(template -> stringBuilder.append(String.format(tableRow,
template.getTemplateId(),
template.getProvider1() != null ? template.getProvider1().getId() : "",
template.getProvider2() != null ? template.getProvider2().getId() : "",
template.getProvider3() != null ? template.getProvider3().getId() : "",
template.getEnv(),
template.getProvider2() != null ? template.getProvider2().getBusinessUnit(): "", // <--
template.getPriority()))
);
I tried to check if all the providers are null and if one of them is not null , then display bussiness unit for that provider

There's a function commonly used in SQL that returns the first non-null parameter called "coalesce". You could write a Java equivalent of that.
Object coalesce(Object... objects) {
for (Object obj : objects) {
if(obj != null) return obj;
}
return null;
}
...
Provider firstNonNullTemplate=(Provider) coalesce(template.getProvider1(), template.getProvider2(), template.getProvider3());

How to get null and filled values from database using hibernate

I am using hibernate to get data from oracle.I have Criterion object to make filter for hibernate select like this
Criterion cr6=null;
if(reqrrn != null)
{
cr6=Restrictions.eq("rrn", reqrrn);//o
}
else{
cr6=Restrictions.like("rrn", "",MatchMode.ANYWHERE);
}
Criterion cr20=null;
if(cardPrefix != null && cardPrefix != "")
{
cr20=Restrictions.eq("prefix", cardPrefix);
}
else{
cr20=Restrictions.like("prefix", "",MatchMode.ANYWHERE);
}
criteria.add(Restrictions.and(cr6, cr20));
i have filters like this, but it is usseless when value is null, for example
cardPrefix value is null in database i want to get all values for cardPrefix ,which are filled and null too, how can i do this ?

i solved it. it will be for all parameters like
if(cardPrefix != null && cardPrefix != "")
{
cr20=Restrictions.eq("prefix", cardPrefix);
}
else{
cr20=Restrictions.like("prefix", "",MatchMode.ANYWHERE);
cr1=Restrictions.isNull("prefix");
cr20=Restrictions.or(cr20, cr1);
}

NullPointerException when using String from SQL database

I am trying to use a String read from a row in an SQL database, but when I do, I get the following NullPointerException :
Exception in thread "main" java.lang.NullPointerException
at ReadCol.data(ReadCol.java:37)
at ReadCol.main(ReadCol.java:50)
My code is shown below...
public String[] array;
ResultSet rs=st.executeQuery("select * from ATTENDANCE");
while(rs.next()){
File file = new File("E:\\eclipse\\workspace\\AutoAttendanceSystem\\res\\AttendanceData.csv");
List<String> lines = Files.readAllLines(file.toPath(), StandardCharsets.UTF_8);
for (String line : lines) {
array = line.split(",");
// This is line 37 :
if(rs.getString(1).equals(array[0]) && rs.getString(7).equals(array[6])){
JOptionPane.showMessageDialog(null, "Can't Update Because record already exist");
}
}
Here is the SQL table's structure :
CREATE TABLE "ATTENDANCE" (
"ATTENDANT_NAME" VARCHAR2(4000),
"ATTENDANT_AGE" NUMBER,
"ATTENDANT_CONTACT_NO" NUMBER,
"ATTENDANT_DEPARTMENT_NAME" VARCHAR2(4000),
"REGISTRATION_NUM" VARCHAR2(50),
"ABSENT_PRESENT" VARCHAR2(4000) DEFAULT 'Absent',
"ATTENDANCE_TIME_DATE" VARCHAR2(4000)
)
And here is an example of a row in that table :
Sun 2016.08.14 at 11:21:43 PM PDT, null, null, Thu 2016.08.18 at 01:58:34 AM PDT, null, Thu 2016.08.18 at 02:13:26 AM PDT, null
What is the problem ?

What is going on
It appears that the problem is when you call rs.getString(7).equals(...) or rs.getString(1).equals : this means that getString has returned null.
This can happen for 2 reasons :
The column that you ask (in that case column 1 or 7) doesn't exist
(doesn't seem to be the case here given your SQL table structure)
a NULL value must have been stored in the column, and getString returns null, which is why calling equals on null throws an exception.
Readings about this :
Information about ResultSet.getString's return value: ResultSet's documentation.
Why calling a method on a reference that points to null throws a NullPointerException
How to solve the problem
First off, to know which column is causing the problem, separate the conditions on 2 lines and see which one throws an exception :
if(rs.getString(1).equals(array[0]) &&
rs.getString(7).equals(array[6])){
If it is ok for your database to hold NULL values, then what you should do, is test for it before applying equals :
if( ( rs.getString(1) == null && array[0] == null
|| rs.getString(1) != null && rs.getString(1).equals(array[0]) )
&& ... // same for 7th column
Side notes
You should refer to columns using their names rather their index.
To make the code easier to understand, you could store the strings you want to compare in variables, and only later test the conditions on these variables.
End result
String databaseResult1, databaseResult2, fileResult1, fileResult2;
// Start looping
// ...
databaseResult1 = rs.getString("ATTENDANT_NAME");
fileResult1 = array[0];
databaseResult2 = rs.getString("ATTENDANCE_TIME_DATE");
fileResult2 = array[6];
if(
( databaseResult1 == null && fileResult1 == null
|| databaseResult1 != null && databaseResult1.equals(fileResult1) )
&&
( databaseResult2 == null && fileResult2 == null
|| databaseResult2 != null && databaseResult2.equals(fileResult2) )
...

Java String appending with comma as a separator

I have a requirement where I need to append multiple values from multiple web service calls into one final string with comma as a separator.
Some of the values might be null, in that case I need to check for not null and then append it as empty string.
If there is no value for one of the string, comma should not get appended.
Please help me resolving this. here is the code what I did.
StringBuilder sb = new StringBuilder();
if (usersList.totalCount != 0 && usersList.totalCount >= 1) {
logger.info("usersList.totalCount ----->"
+ usersList.totalCount);
for (KalturaUser user : usersList.objects) {
if (user.id != null) {
sb.append(userId);
}
if (user.firstName != null) {
sb.append(",").append(userFirstName);
}
if (user.lastName != null) {
sb.append(",").append(user.lastName);
}
if (user.email != null) {
sb.append(",").append(user.email);
}
if (user.roleNames != null) {
sb.append(",").append(user.roleNames);
}
if (user.partnerData != null) {
sb.append(",").append(user.partnerData);
}
}
System.out.println(sb);
}
Thanks,
Raji

I think you are looking for something like this:
public static String asString(Object value) {
return value == null ? "" : value.toString();
}
for (KalturaUser user : usersList.objects) {
sb.append(asString(user.id));
sb.append(",").append(asString(user.firstName));
sb.append(",").append(asString(user.lastName));
sb.append(",").append(asString(user.email));
sb.append(",").append(asString(user.roleNames));
sb.append(",").append(asString(user.partnerData));
}

Well, in your tests like
if (user.id != null) {
sb.append(userId);
}
you are checking user.id but appending userId. These are two different variables.
You should probably change it into
if (user.id != null) {
sb.append(user.id); //instead of sb.append(userId);
}

It is not clear what your problem is, but if you are looking for a better or different approach, I found that it is best to append to a List<String> and then use StringUtils.join to produce the final string.

You can use a class from a google library called Joiner.
String concatenedString = Joiner.on(",").skipNulls().join(itemToAdd);
You can find this class on google-collections-1.0.jar

I would do something like that. It's based on Java8 streams, but here you don't need to do the non-null check on every property(.filter does this for you). I assumed that users.object is an array list, if it's not you might need to convert it into stream in other way
if (userList.totalCount > 0) {
logger.info("usersList.totalCount ----->" + usersList.totalCount);
String result = userList
.objects
.stream()
.map(user -> {
return Stream.of(user.firstName, user.id, user.lastName, user.email, user.roleNames, user.partnerData) //get the properties you need into the stream
.filter(property -> property != null) // filter out null properties
.collect(Collector.joining(",")); //join them by comma
})
.collect(Collector.joining(",")); //join user strings with comma
System.out.println(result);
}

Using Jackcess to retrieve numeric values stored in a text field gives ClassCastException

I am working with Jackcess to read and categorize an access database. It's simply meant to open the database, loop through each line, and print out individual row data to the console which meet certain conditions. It works fine, except for when I try to read numeric values. My code is below. (This code is built into a Swing GUI and gets executed when a jbutton is pressed.)
if (inv == null) { // Check to see if inventory file has been set. If not, then set it to the default reference path.
inv = rPath;
}
if (inventoryFile.exists()) { // Check to see if the reference path exists.
List<String> testTypes = jList1.getSelectedValuesList();
List<String> evalTypes = jList3.getSelectedValuesList();
List<String> grainTypes = jList2.getSelectedValuesList();
StringBuilder sb = new StringBuilder();
for (int i=0; i<=evalTypes.size()-1; i++) {
if (i<evalTypes.size()-1) {
sb.append(evalTypes.get(i)).append(" ");
}
else {
sb.append(evalTypes.get(i));
}
}
String evalType = sb.toString();
try (Database db = DatabaseBuilder.open(new File(inv));) {
Table sampleList = db.getTable("NTEP SAMPLES LIST");
Cursor cursor = CursorBuilder.createCursor(sampleList);
for (int i=0; i<=testTypes.size()-1; i++) {
if ("Sample Volume".equals(testTypes.get(i))) {
if (grainTypes.size() == 1 && "HRW".equals(grainTypes.get(0))) {
switch (evalType) {
case "GMM":
for (Row row : sampleList){
if (null != row.getString("CURRENTGAC")) {}
if ("HRW".equals(row.get("GRAIN")) && row.getDouble("CURRENTGAC")>=12.00) {
System.out.print(row.get("GRAIN") + "\t");
System.out.println(row.get("CURRENTGAC"));
}
}
break;
case "NIRT":
// some conditional code
break;
case "TW":
// some more code
break;
}
}
else {
JOptionPane.showMessageDialog(null, "Only HRW samples can be used for the selected test(s).", "Error", JOptionPane.ERROR_MESSAGE);
}
break;
}
}
}
catch (IOException ex) {
Logger.getLogger(SampleFilterGUI.class.getName()).log(Level.SEVERE, null, ex);
}
When the code is run I get the following error:
java.lang.ClassCastException: java.lang.String cannot be cast to java.lang.Double
The following condition looks to be what is throwing the error.
row.getDouble("CURRENTGAC")>=12.00
It appears that when the data is read from the database, the program is reading everything as a string, even though some fields are numeric. I was attempting to cast this field as a double, but java doesn't seem to like that. I have tried using the Double.parseDouble() and Double.valueOf() commands to try converting the value (as mentioned here) but without success.
My question is, how can I convert these fields to numeric values? Is trying to type cast the way to go, or is there a different method I'm not aware of? You will also notice in the code that I created a cursor, but am not using it. The original plan was to use it for navigating through the database, but I found some example code from the jackcess webpage and decided to use that instead. Not sure if that was the right move or not, but it seemed like a simpler solution. Any help is much appreciated. Thanks.
EDIT:
To ensure the program was reading a string value from my database, I input the following code
row.get("CURRENTGAC").getClass().getName()
The output was java.lang.String, so this confirms that it is a string. As was suggested, I changed the following code
case "GMM":
for (Row row : sampleList){
if (null != row.get("CURRENTGAC"))
//System.out.println(row.get("CURRENTGAC").getClass().getName());
System.out.println(String.format("|%s|", row.getString("CURRENTGAC")));
/*if ("HRW".equals(row.get("GRAIN")) && row.getDouble("CURRENTGAC")>=12.00 && row.getDouble("CURRENTGAC")<=14.00) {
System.out.print(row.get("GRAIN") + "\t");
System.out.println(row.get("CURRENTGAC"));
}*/
}
break;
The ouput to the console from these changes is below
|9.85|
|11.76|
|9.57|
|12.98|
|10.43|
|13.08|
|10.53|
|11.46|
...
This output, although looks numeric, is still of the string type. So when I tried to run it with my conditional statement (which is commented out in the updated sample code) I still get the same java.lang.ClassCastException error that I was getting before.

Jackcess does not return all values as strings. It will retrieve the fields (columns) of a table as the appropriate Java type for that Access field type. For example, with a test table named "Table1" ...
ID DoubleField TextField
-- ----------- ---------
1 1.23 4.56
... the following Java code ...
Table t = db.getTable("Table1");
for (Row r : t) {
Object o;
Double d;
String fieldName;
fieldName = "DoubleField";
o = r.get(fieldName);
System.out.println(String.format(
"%s comes back as: %s",
fieldName,
o.getClass().getName()));
System.out.println(String.format(
"Value: %f",
o));
System.out.println();
fieldName = "TextField";
o = r.get(fieldName);
System.out.println(String.format(
"%s comes back as: %s",
fieldName,
o.getClass().getName()));
System.out.println(String.format(
"Value: %s",
o));
try {
d = r.getDouble(fieldName);
} catch (Exception x) {
System.out.println(String.format(
"r.getDouble(\"%s\") failed - %s: %s",
fieldName,
x.getClass().getName(),
x.getMessage()));
}
try {
d = Double.parseDouble(r.getString(fieldName));
System.out.println(String.format(
"Double.parseDouble(r.getString(\"%s\")) succeeded. Value: %f",
fieldName,
d));
} catch (Exception x) {
System.out.println(String.format(
"Double.parseDouble(r.getString(\"%s\")) failed: %s",
fieldName,
x.getClass().getName()));
}
System.out.println();
}
... produces:
DoubleField comes back as: java.lang.Double
Value: 1.230000
TextField comes back as: java.lang.String
Value: 4.56
r.getDouble("TextField") failed - java.lang.ClassCastException: java.lang.String cannot be cast to java.lang.Double
Double.parseDouble(r.getString("TextField")) succeeded. Value: 4.560000
If you are unable to get Double.parseDouble() to parse the string values from your database then either
they contain "funny characters" that are not apparent from the samples you posted, or
you're doing it wrong.
Additional information re: your sample file
Jackcess is returning CURRENTGAC as String because it is a Text field in the table:
The following Java code ...
Table t = db.getTable("NTEP SAMPLES LIST");
int countNotNull = 0;
int countAtLeast12 = 0;
for (Row r : t) {
String s = r.getString("CURRENTGAC");
if (s != null) {
countNotNull++;
Double d = Double.parseDouble(s);
if (d >= 12.00) {
countAtLeast12++;
}
}
}
System.out.println(String.format(
"Scan complete. Found %d non-null CURRENTGAC values, %d of which were >= 12.00.",
countNotNull,
countAtLeast12));
... produces ...
Scan complete. Found 100 non-null CURRENTGAC values, 62 of which were >= 12.00.