Develop Reference

Stream Filter List based on Combination of values from another List

Need: To filter out data in list - 1 based on the values present in list - 2 with multiple criteria i.e. combination of Date & Order Number
Issue: Able to filter based on 1 criteria. But when I try adding another filter condition it treats it as 2 separate & not as combination. Unable to figure out how to make it as a combination.
Hope issue faced is clear.
Research: I referred to my earlier query on similar need - Link1 . Also checked - Link2
List 1: (All Orders)
[Date | OrderNumber | Time | Company | Rate ]
[2014-10-01 | 12345 | 10:00:01 | CompA | 1000]
[2015-03-01 | 23456 | 08:00:01 | CompA | 2200]
[2016-08-01 | 34567 | 09:00:01 | CompA | 3300]
[2017-09-01 | 12345 | 11:00:01 | CompA | 4400]
[2017-09-01 | 98765 | 12:00:01 | CompA | 7400]
List 2: (Completed Orders)
[Date | OrderNumber | Time]
[2014-10-01 | 12345 | 10:00:01]
[2015-03-01 | 23456 | 08:00:01]
[2016-08-01 | 34567 | 09:00:01]
[2017-09-01 | 98765 | 12:00:01]
Expected O/p after filter :
[Date | OrderNumber | Time | Company | Rate]
[2017-09-01 | 12345 | 11:00:01 | CompA | 4400]
Code:
// Data extracted from MySQL database
// List 1: All Orders
List<ModelAllOrders> listOrders = getDataFromDatabase.getTable1();
// List 2: Completed Orders
List<ModelCompletedOrders> listCompletedOrders = getDataFromDatabase.getTable2();
// Filter with 1 criteria works
Set<Integer> setOrderNumbers = listCompletedOrders.stream().map(ModelCompletedOrders::getOrderNumber).collect(Collectors.toSet());
listOrders = listOrders.stream().filter(p -> !setOrderNumbers.contains(p.getOrderNumber()).collect(Collectors.toList());
// Below not working as expected when trying to combinational filter
Set<LocalDate> setDates = listCompletedOrders.stream().map(ModelCompletedOrders::getDate).collect(Collectors.toSet());
listOrders = listOrders.stream().filter(p -> !setDates.contains(p.getDate()) && !setOrderNumbers.contains(p.getOrderNumber()))
.collect(Collectors.toList());

You've asked for logic that will do this:
The combination of Date & Order Number is unique. I need to check if that unique combination is present in List-2, if yes then filter out, if not then output should contain that row.
Stream::filter() will return a subset of the stream where the filter predicate returns true (i.e. it filters out those objects in the stream where the predicate is false).
listOrders = listOrders.stream().filter(p -> !setDates.contains(p.getDate()) && !setOrderNumbers.contains(p.getOrderNumber()))
.collect(Collectors.toList());
Your code expression here says "show me orders where the order's date does not appear in the list of prior orders AND where the order's order number does not appear in the list of prior orders". Your logical expression is wrong (you're getting confused between what in electronics would be called positive vs negative logic).
You want either:
listOrders = listOrders.stream().filter(p -> !(setDates.contains(p.getDate()) && setOrderNumbers.contains(p.getOrderNumber())))
.collect(Collectors.toList());
"show me orders where both the order's date and order's id are not
present in the list of prior orders"
or:
listOrders = listOrders.stream().filter(p -> !setDates.contains(p.getDate()) || !setOrderNumbers.contains(p.getOrderNumber()))
.collect(Collectors.toList());
"show me orders where either the order's date has not been seen before
OR the order's id has not been seen before"

Java - Gherkin & Cucumber: Pass an object or list of objects on a vertical table instead of horizontal

I have the following sample gherkin scenario on my feature file:
Scenario: Book an FX Trade
Given trades with the following details are created:
|buyCcy |sellCcy |amount |date |
|EUR |USD |12345.67 |23-11-2017 |
|GBP |EUR |67890.12 |24-11-2017 |
When the trades are executed
Then the trades are confirmed
In my glue file, I can map the data table to an object Trade as an out of the box cucumber solution:
#When("^trades with the following details are created:$")
public void trades_with_the_following_details_are_created(List<Trade> arg1) throws Throwable {
//do something with arg1
}
What I want to achieve:
Improve the readability of my gherkin scenario by doing the following:
Transpose the data table vertically, This will improve readability if my object has around 10 fields
Replace fields / column names with aliases
Sample:
Scenario: Book an FX Trade
Given trades with the following details are created:
|Buy Currency | EUR | GBP |
|Sell Currency | USD | EUR |
|Amount | 12345.67 | 67890.12 |
|Date | 23-11-2017 | 24-11-2017 |
When the trades are executed
Then the trades are confirmed
I want the table to be dynamic in a way that it can have more or less than 2 data sets / columns. What would be the best way to achieve this?
Additional info:
Language: Java 8
Cucumber version: 1.2.5
Trade POJO being something like:
public class Trade {
private String buyCcy;
private String sellCcy;
private String amount;
private String date;
/**
* These fields are growing and may have around 10 or more....
* private String tradeType;
* private String company;
*/
public Trade() {
}
/**
* accessors here....
*/
}

If the table is specified in your feature file as
|buyCcy | EUR | GBP |
|sellCcy | USD | EUR |
|amount | 12345.67 | 67890.12 |
|date | 23-11-2017 | 24-11-2017 |
you can use the following glue code (with your posted Trade class, assuming that there is a proper toString() method implemented)
#Given("^trades with the following details are created:$")
public void tradeWithTheFollowingDetailsAreCreated(DataTable dataTable) throws Exception {
// transpose - transposes the table from the feature file
// asList - creates a `List<Trade>`
List<Trade> list = dataTable.transpose().asList(Trade.class);
list.stream().forEach(System.out::println);
}
output
Trade{buyCcy=EUR, sellCcy=USD, amount=12345.67, date=23-11-2017}
Trade{buyCcy=GBP, sellCcy=EUR, amount=67890.12, date=24-11-2017}

Hibernate HQL query extract missing ids entity

I think that the title of the question might be misunderstood, so I'll explain all the workflow.
I have a select2 which allows me to find all the missing document numbers from a documents list controller in the back-end. Atm I've implemented a method in which hibernate returns me the current documents list and, by iterating it, the method populates another list with a "fake" document with the missing number.
I wanted to know if it is possibile to translate this workflow in an HQL query which returns me back a new list of documents with the missing numbers.
EXAMPLE:
Base table:
| id | number |
---------------
| 1 | 1 |
---------------
| 8 | 3 |
---------------
| 9 | 4 |
---------------
| 12 | 8 |
My Select2 will receive back a documentsList like this
{
model: {id: 2, number: 2},
model: {id: 5, number: 5}
model: {id: 6, number: 6}
model: {id: 7, number: 7}
}
I hope this question is clear enough,
Thanks everyone in advance
EDIT 2016/05/02
This is the code I've implemented.
HQLQueryProperties is a class I've created to setup the HQL query executed by the DAO, which is called by the service (It's a Struts2 + Hibernate + Spring application). Anyway this part is not so important, since the DAO can execute normal HQLQueries or extract the query from the HQLQueryProperties object
HQLQueryProperties invoicesProperties = new HQLQueryProperties();
Map<String, Object> invoicesAttributes = invoicesProperties
.addJoinAttributes("documentType")
.addWhereAttribute("listByOperationYear", "and", null)
.addWhereAttribute("listByDocumentTypeId", "and", null)
.addWhereAttribute("listByFacilityIds", "and", null)
.addWhereAttribute("excludeNumbers", "and", null)
.addQueryAttribute("operationYear", ((Map<String, Object>) session.get("operationYear")).get("selectedYear"))
.addQueryAttribute("documentTypeId", documentTypeId)
.addQueryAttribute("facilityIds", -1, ((Facility) session.get("facility")).getId())
.addQueryAttribute("numbers", -1)
.buildAttributes();
The paginator is another class I've created to setup the resulting jsp with a table which can be customized by the user which interact with this object. The method getItems() calls the required service/DAO and returns a List<MyClass> of items. It's also used to paginate the Select2 results
Paginator paginator = new Paginator("documentHeaderService", servletContext, getColumns("documentHeaderService"), invoicesAttributes, false);
paginator.setPerPage(-1);
paginator.setOrderColumn("number");
List<DocumentHeader> tempDocuments = paginator.getItems();
And here is the tricky part where I iterate over the collection in order to retrieve the missing number.
int currentNumber = 1;
for (DocumentHeader tempDocument : tempDocuments) {
while (currentNumber < tempDocument.getNumber()) {
freeNumbersList.add(new DocumentHeader(currentNumber));
currentNumber++;
}
currentNumber++;
}

Changing Mocked ResultSet value each time a SQL statement is run

I'm using Mockrunner to create a mock result set for a select statement. I have a loop that executes the select statement (which returns a single value). I want to have the result set return a different value each time, but I have been unable to find anything about how to specify the result set return value based on the times the statement has been called. Here's a pseudocode snippet of the code:
In the test Code:
String selectSQL = "someselectStmt";
StatementResultSetHandler stmtHandler = conn.GetStatementResultSetHandler();
MockResultSet result = stmtHandler.createResultSet();
result.addRow(new Integer[]{new Integer(1)});
stmtHandler.prepareResultSet(selectSQL, result);
In the Actual Target Class:
Integer[] Results = getResults(selectSQL);
while(Results.length != 0){
//do some stuff that change what gets returned in the select stmt
Results = getResults(selectSQL)
}
So essentially I'd like to return something like 1 on the first time through, 2 on the 2nd and nothing on the 3rd. I haven't found anything so far that I'd be able to leverage that could achieve this. The mocked select statement will always return whatever the last result set was to be associated with it (for instance if I created two MockResultSets and associated both with the same select stmt). Is this idea possible?

Looping Control Flow Working Within Java and SQL
If you're coding this one in Java, a way to make your code execution calls return different, sequenced results can be accomplished throughh a looping control flow statement such as a do-while-loop. This Wikipedia reference has a good discussion using the contrast of the do-while-loop between implementations in Java and also in different programming lanugages.
Some Additional Influences through Observation:
A clue from your work with the Mockrunner tool:
The mocked select statement will always return whatever the last result set was to be associated with it (for instance if I created two MockResultSets and associated both with the same select stmt)
This is the case because the SELECT statement must actually change as well or else repeating the query will also repeat the result output. A clue is that your SQL exists as a literal string value throughout the execution of the code. Strings can be altered through code and simple string manipulations.
String selectSQL = "someselectStmt";
StatementResultSetHandler stmtHandler = conn.GetStatementResultSetHandler();
MockResultSet result = stmtHandler.createResultSet();
result.addRow(new Integer[]{new Integer(1)});
stmtHandler.prepareResultSet(selectSQL, result);
in addition to the selectSQL variable, also add a line for a numeric variable to keep track of how many times the SQL statement is executed:
Int queryLoopCount = 0;
In the following target class:
Integer[] Results = getResults(selectSQL);
while(Results.length != 0){
//do some stuff that change what gets returned in the select stmt
Results = getResults(selectSQL)
}
Try rewriting this WHILE loop control following this example. In your pseudocode, you will keep pulling the same data from the call to getResults(selectSQL); because the query remains the same through every pass made through the code.
Setting up the Test Schema and Example SQL Statement
Here is a little workup using a single MySQL table that contains "testdata" output to be fed into some result set. The ID column could be a way of uniquely identifying each different record or "test case"
SQL Fiddle
MySQL 5.5.32 Schema Setup:
CREATE TABLE testCaseData
(
id int primary key,
testdata_col1 int,
testdata_col2 varchar(20),
details varchar(30)
);
INSERT INTO testCaseData
(id, testdata_col1, testdata_col2, details)
VALUES
(1, 2021, 'alkaline gab', 'First Test'),
(2, 322, 'rebuked girdle', '2nd Test'),
(3, 123, 'municipal shunning', '3rd Test'),
(4, 4040, 'regal limerick', 'Skip Test'),
(5, 5550, 'admonished hundredth', '5th Test'),
(6, 98, 'docile pushover', '6th Test'),
(7, 21, 'mousiest festivity', 'Last Test');
commit;
Query 1 A Look at All the Test Data:
SELECT id, testdata_col1, testdata_col2, details
FROM testCaseData
Results:
| ID | TESTDATA_COL1 | TESTDATA_COL2 | DETAILS |
|----|---------------|----------------------|------------|
| 1 | 2021 | alkaline gab | First Test |
| 2 | 322 | rebuked girdle | 2nd Test |
| 3 | 123 | municipal shunning | 3rd Test |
| 4 | 4040 | regal limerick | Skip Test |
| 5 | 5550 | admonished hundredth | 5th Test |
| 6 | 98 | docile pushover | 6th Test |
| 7 | 21 | mousiest festivity | Last Test |
Query 2 Querying Only the First Record in the Table:
SELECT id, testdata_col1, testdata_col2, details
FROM testCaseData
WHERE id = 1
Results:
| ID | TESTDATA_COL1 | TESTDATA_COL2 | DETAILS |
|----|---------------|---------------|------------|
| 1 | 2021 | alkaline gab | First Test |
Query 3 Querying a Specific Test Record Within the Table:
SELECT id, testdata_col1, testdata_col2, details
FROM testCaseData
WHERE id = 2
Results:
| ID | TESTDATA_COL1 | TESTDATA_COL2 | DETAILS |
|----|---------------|----------------|----------|
| 2 | 322 | rebuked girdle | 2nd Test |
Query 4 Returning and Limiting the Output Set Size:
SELECT id, testdata_col1, testdata_col2, details
FROM testCaseData
WHERE id < 5
Results:
| ID | TESTDATA_COL1 | TESTDATA_COL2 | DETAILS |
|----|---------------|--------------------|------------|
| 1 | 2021 | alkaline gab | First Test |
| 2 | 322 | rebuked girdle | 2nd Test |
| 3 | 123 | municipal shunning | 3rd Test |
| 4 | 4040 | regal limerick | Skip Test |
Writing a Parameterized SQL Statement
I do not know if this difference in syntax yields the exact same results as your pseudocode, but I am recommending it from references of code structures that I know already work.
set condition value before loop
do{
// do some work
// update condition value
}while(condition);
The WHILE condition is instead at the end of the statement and should be based on a change to a value made within the looping block. We will now introduce the second variable, an int which tracks the number of times that the loop is iterated over:
String selectSQL = "someselectStmt";
String[] Results; = getResults(selectSQL);
// set condition value before loop
queryLoopCount = 0
do{
// do some work
Results = getResults(selectSQL);
// update condition value
queryLoopCount = queryLoopcount + 1;
}while(queryLoopCount < 6);
Where selectSQL comes from:
SELECT id, testdata_col1, testdata_col2, details
FROM testCaseData
WHERE id = 2;
And adapts with a built in parameter to:
selectSQL = 'SELECT id, testdata_col1, testdata_col2, details
FROM testCaseData
WHERE id = ' + queryLoopCount;
Mixing the string and integer values may not be a problem as in this reference on concatenated(+) values suggests: Anything concatenated to a string is converted to string (eg, "weight = " + kilograms).
Ideas for Specialized Case Requirements
You could introduce your own numbering sequence to get the records of each case to cycle through the reference table. There are a lot of possibilities by introducing an ORDER BY statement and altering the key ORDER BY value.
The "Skip" case. Within the Do-While loop, add a IF-THEN statement to conditionally skip a specific record.
set condition value before loop
do{
if ( queryLoopCount <> 4 ) {
// do some work}
// update condition value
queryLoopCount = queryLoopCount + 1;
}while(condition);
Using an if-then loop, this code sample will process all test records but will skip over the record of ID = 4 and continue through until the while loop condition is met.

Query Database, Rearrange, Insert into new table

I already have a database with every user's scores and other stats. But the scores aren't organized in any way that make it usable to make a leaderboard rank.
If the table looks something like this:
+----------+-------+-----+
| Username | Score | ... |
+----------+-------+-----+
| UserA | 900 | ... |
+----------+-------+-----+
| UserB | 200 | ... |
+----------+-------+-----+
| UserC | 850 | ... |
+----------+-------+-----+
| UserD | 450 | ... |
+----------+-------+-----+
There is no relation to position in the database and score. Now, what I want to do is create a query of the database collecting the scores for each user, then rearranging them by score. I figure this would be something like ORDER BY score DESC.
After ordering them in the correct way, I want to input the new values into a table with only username and rank, which I can query ingame to tell the rank of any given player requested.
ex:
+----------+------+
| Username | Rank |
+----------+------+
| UserA | 1 |
+----------+------+
| UserC | 2 |
+----------+------+
| UserD | 3 |
+----------+------+
| UserB | 4 |
+----------+------+
Now if I quered rank where username=UserA I would get 1
So what is my question? How do I, in java, query the database for score & username then rearrange the values into a new table based on the numerical rank, not score.

For specific user, this might work:
select username, score, (select count(h.username)+1 from users u, (select username, score from users) h where u.username = 'UserG' and (h.score > u.score)) as 'rating' from users where username = 'UserG';
Problem with setting a variable #rank like Alain suggested would be in case of duplicate scores, what if 2 users have a score of 100? Query above will rate them both as #5, if that is what you need.

The "In Java" is the only confusing part of your question. You want something like:
CREATE TABLE leaderboard (username varchar(50), score int unsigned, rank int unsigned)
INSERT INTO leaderboard (username, score, rank) SELECT username, score, #rank:=#rank+1 FROM scores_table, (SELECT #rank:=0) as run_once order by rank desc;
Untested, but that would be the concept. When it comes time to recalculate the leaderboard just:
DELETE * from leaderboard;
INSERT INTO leaderboard (username, score, rank) SELECT username, score, #rank:=#rank+1 FROM scores_table, (SELECT #rank:=0) as run_once order by score desc;

Make the database, um, return the data you need in the format you want:
set #rank = 0;
select username, #rank := #rank + 1 as rank
from user_scores
order by score desc
No Java magic required.

There was a similar discussion in this thread.
In general it's better to just select ordering by score and then put the query result into an array list. 0th item would be the person with the best score, 1st item person with second score, etc.
If you really need to select with ranking in the result set try using one of the examples in the linked discussion.