GroupByTest.java

package net.sourceforge.mayfly.evaluation;

import static net.sourceforge.mayfly.evaluation.select.Evaluator.NO_SUBSELECT_NEEDED;

import junit.framework.TestCase;

import net.sourceforge.mayfly.datastore.LongCell;
import net.sourceforge.mayfly.evaluation.expression.SingleColumn;
import net.sourceforge.mayfly.util.ImmutableList;
import net.sourceforge.mayfly.util.MayflyAssert;

import java.util.Iterator;

public class GroupByTest extends TestCase {
    
    public void testGroup() throws Exception {
        GroupBy groupBy = new GroupBy(new GroupItem(new SingleColumn("a")));
        ResultRows rows = new ResultRows(
            new ImmutableList()
                .with(new ResultRow()
                    .withColumn("foo", "a", new LongCell(7))
                    .withColumn("foo", "b", new LongCell(50))
                )
                .with(new ResultRow()
                    .withColumn("foo", "a", new LongCell(7))
                    .withColumn("foo", "b", new LongCell(51))
                )
                .with(new ResultRow()
                    .withColumn("foo", "a", new LongCell(8))
                    .withColumn("foo", "b", new LongCell(52))
                )
        );
        
        GroupedRows grouped = groupBy.makeGroupedRows(rows, NO_SUBSELECT_NEEDED);
        assertEquals(2, grouped.groupCount());

        Iterator iterator = grouped.iteratorForFirstKeys();
        assertEquals(new LongCell(7), iterator.next());
        assertEquals(new LongCell(8), iterator.next());
        assertFalse(iterator.hasNext());
        
        ResultRows sevenRows = 
            grouped.getRows(new GroupByCells(new LongCell(7)));

        assertEquals(2, sevenRows.rowCount());
        expectRow(7, 50, sevenRows.row(0));
        expectRow(7, 51, sevenRows.row(1));

        ResultRows eightRows =
            grouped.getRows(new GroupByCells(new LongCell(8)))
        ;
        expectRow(8, 52, eightRows.singleRow());
    }

    private void expectRow(int expectedA, int expectedB, ResultRow fifty) {
        MayflyAssert.assertColumn("foo", "a", expectedA, fifty, 0);
        MayflyAssert.assertColumn("foo", "b", expectedB, fifty, 1);
    }

    public void testMutiple() throws Exception {
        GroupBy groupBy = new GroupBy(
            new GroupItem(new SingleColumn("a")),
            new GroupItem(new SingleColumn("b"))
        );
        ResultRows rows = new ResultRows(
            new ImmutableList()
                .with(new ResultRow()
                    .withColumn("foo", "a", new LongCell(7))
                    .withColumn("foo", "b", new LongCell(50))
                    .withColumn("foo", "c", new LongCell(400))
                )
                .with(new ResultRow()
                    .withColumn("foo", "a", new LongCell(7))
                    .withColumn("foo", "b", new LongCell(51))
                    .withColumn("foo", "c", new LongCell(400))
                )
                .with(new ResultRow()
                    .withColumn("foo", "a", new LongCell(8))
                    .withColumn("foo", "b", new LongCell(51))
                    .withColumn("foo", "c", new LongCell(300))
                )
        );
        
        GroupedRows grouped = groupBy.makeGroupedRows(rows, NO_SUBSELECT_NEEDED);
        assertEquals(3, grouped.groupCount());

        Iterator iterator = grouped.iteratorForFirstKeys();
        assertEquals(new LongCell(7), iterator.next());
        assertEquals(new LongCell(7), iterator.next());
        assertEquals(new LongCell(8), iterator.next());
        assertFalse(iterator.hasNext());
        
        ResultRows seven50 = 
            grouped.getRows(new GroupByCells(new LongCell(7), new LongCell(50)))
        ;
        ResultRow seven50Row = seven50.singleRow();
        MayflyAssert.assertColumn("foo", "a", 7, seven50Row, 0);
        MayflyAssert.assertColumn("foo", "b", 50, seven50Row, 1);
        MayflyAssert.assertColumn("foo", "c", 400, seven50Row, 2);

        ResultRows seven51 =
            grouped.getRows(new GroupByCells(new LongCell(7), new LongCell(51)))
        ;
        ResultRow seven51Row = seven51.singleRow();
        MayflyAssert.assertColumn("foo", "a", 7, seven51Row, 0);
        MayflyAssert.assertColumn("foo", "b", 51, seven51Row, 1);
        MayflyAssert.assertColumn("foo", "c", 400, seven51Row, 2);
    }

}