Scalar Collections

Scalar collections contain simple data types like Integer, Long, Float, Double and Boolean. They can be managed by the PgxSession APIs:

Creation of a Scalar Collection

You can use createSet() and createSequence() methods to create a scalar collection as shown in the following code:

myIntSet = session.createSet(PropertyType.INTEGER, "myIntSet")
myDoubleSequence = session.createSequence(PropertyType.DOUBLE)  // A name will be automatically generated if none is provided.
println myDoubleSequence.getName()                              // Display the generated name.

import oracle.pgx.api.*;
import oracle.pgx.common.types.*;
...
ScalarSet myIntSet = session.createSet(PropertyType.INTEGER, "myIntSet");
ScalarSequence myDoubleSequence = session.createSequence(PropertyType.DOUBLE);
System.out.println(myDoubleSequence.getName());

Run Operations on a Scalar Collection

You can run several operations on a scalar collection as shown in the following code:

myIntSet.add(10)
myIntSet.addAll([0, 1, 2, 3, 4, 5, 6, 7, 8, 9])
myIntSet.addAll([0,1,2])                // Element uniqueness. This operation has no effect on the set.
println myIntSet

myIntSet.contains(1)                   // Checks the presence of an element. This code returns `true`.
myIntSet.remove(10)
myIntSet.removeAll([4, 5, 6, 7, 8, 9]) // Leaves only elements `0, 1, 2, 3`.
println  myIntSet

import java.util.Arrays;
import oracle.pgx.api.*;
...
myIntSet.add(10);
myIntSet.addAll(Arrays.asList(0, 1, 2, 3, 4, 5, 6, 7, 8, 9));
myIntSet.addAll(Arrays.asList(0, 1, 2));

myIntSet.contains(1);  // Returns `true`.
myIntSet.remove(10);
myIntSet.removeAll(Arrays.asList(4, 5, 6, 7, 8, 9));

Traversal of a Scalar Collection

You can traverse a scalar collection either using an iterator or using the new Stream API. You can add elements of a sequence to a set, traverse a sequence and filter out elements not required, and then add the rest to another scalar collection.

myIntSet.forEach({x -> print x + "\n"})
myIntSet.stream().filter({x -> x % 2 == 0}).forEach({x -> myDoubleSequence.add(x)})
println myDoubleSequence

import java.util.Iterator;
import java.util.stream.Stream;
import oracle.pgx.api.*;
...
myIntSet.forEach(x -> System.out.println(x));
myIntSet.stream().filter(x -> x % 2 == 0).forEach(myDoubleSequence::add);