+
−package nl.cwi.monetdb.embedded.tables;
+
−
+
−import nl.cwi.monetdb.embedded.mapping.AbstractRowSet;
+
−import nl.cwi.monetdb.embedded.mapping.MonetDBRow;
+
−
+
−/**
+
− * The iterator class for a MonetDB table. It's possible to inspect the current currentColumns in the row as well
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− * their mappings.
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− *
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− * @author <a href="mailto:pedro.ferreira@monetdbsolutions.com">Pedro Ferreira</a>
+
− */
+
−public class RowIterator extends AbstractRowSet {
+
−
+
−    /**
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−     * The original table of this iterator.
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−     */
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−    protected final MonetDBTable table;
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−
+
−    /**
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−     * The current table row number on the fetched set.
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−     */
+
−    protected int currentIterationNumber;
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−
+
−    /**
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−     * The first row in the table to iterate.
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−     */
+
−    protected final int firstIndex;
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−
+
−    /**
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−     * The last row in the table to iterate.
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−     */
+
−    protected final int lastIndex;
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−
+
−    protected RowIterator(MonetDBTable table, Object[][] rows, int firstIndex, int lastIndex) {
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−        super(table.getMappings(), rows);
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−        this.table = table;
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−        this.firstIndex = firstIndex;
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−        this.lastIndex = lastIndex;
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−        this.currentIterationNumber = -1;
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−    }
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−
+
−    /**
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−     * Gets the original table of this iterator.
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−     *
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−     * @return The original table of this iterator
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−     */
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−    public MonetDBTable getTable() { return table; }
+
−
+
−    /**
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−     * Gets the first index used on this iteration.
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−     *
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−     * @return The first index used on this iteration
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−     */
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−    public int getFirstIndex() { return firstIndex; }
+
−
+
−    /**
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−     * Gets the last index used on this iteration.
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−     *
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−     * @return The last index used on this iteration
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−     */
+
−    public int getLastIndex() { return lastIndex; }
+
−
+
−    /**
+
−     * Gets the current iteration number.
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−     *
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−     * @return The current iteration number
+
−     */
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−    public int getCurrentIterationNumber() { return currentIterationNumber; }
+
−
+
−    /**
+
−     * Gets the current row number of the table in the iteration.
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−     *
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−     * @return The current row number of the table in the iteration
+
−     */
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−    public int getCurrentTableRowNumber() { return this.firstIndex + this.currentIterationNumber; }
+
−
+
−    /**
+
−     * Gets the current row currentColumns values as Java objects.
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−     *
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−     * @return The current row currentColumns values as Java objects
+
−     */
+
−    public MonetDBRow getCurrentRow() { return this.rows[this.currentIterationNumber]; }
+
−
+
−    /**
+
−     * Checks if there are more rows to iterate after the current one.
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−     *
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−     * @return There are more rows to iterate
+
−     */
+
−    public boolean hasMore() { return this.currentIterationNumber + this.firstIndex < this.lastIndex; }
+
−
+
−    /**
+
−     * Gets a column value as a Java class.
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−     *
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−     * @param <T> A Java class mapped to a MonetDB data type
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−     * @param index The index of the column
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−     * @param javaClass The Java class
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−     * @return The column value as a Java class
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−     */
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−    public <T> T getColumnByIndex(int index, Class<T> javaClass) {
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−        return javaClass.cast(this.getCurrentRow().getColumnByIndex(index, javaClass));
+
−    }
+
−
+
−    /**
+
−     * Gets a column value as a Java class using the default mapping.
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−     *
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−     * @param <T> A Java class mapped to a MonetDB data type
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−     * @param index The index of the column
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−     * @return The column value as a Java class
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−     */
+
−    public <T> T getColumnByIndex(int index) {
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−        Class<T> javaClass = this.mappings[index].getJavaClass();
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−        return javaClass.cast(this.getCurrentRow().getColumnByIndex(index));
+
−    }
+
−
+
−    /**
+
−     * Gets a column value as a Java class.
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−     *
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−     * @param <T> A Java class mapped to a MonetDB data type
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−     * @param name The name of the column
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−     * @param javaClass The Java class
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−     * @return The column value as a Java class
+
−     */
+
−    public <T> T getColumnByName(String name, Class<T> javaClass) {
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−        String[] colNames = this.getTable().getColumnNames();
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−        int index = 0;
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−        for (String colName : colNames) {
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−            if (name.equals(colName)) {
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−                return this.getColumnByIndex(index, javaClass);
+
−            }
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−            index++;
+
−        }
+
−        throw new ArrayIndexOutOfBoundsException("The column is not present in the result set!");
+
−    }
+
−
+
−    /**
+
−     * Gets a column value as a Java class using the default mapping.
+
−     *
+
−     * @param <T> A Java class mapped to a MonetDB data type
+
−     * @param name The name of the column
+
−     * @return The column value as a Java class
+
−     */
+
−    public <T> T getColumnByName(String name) {
+
−        String[] colNames = this.getTable().getColumnNames();
+
−        int index = 0;
+
−        for (String colName : colNames) {
+
−            if (name.equals(colName)) {
+
−                return this.getColumnByIndex(index);
+
−            }
+
−            index++;
+
−        }
+
−        throw new ArrayIndexOutOfBoundsException("The column is not present in the result set!");
+
−    }
+
−
+
−    /**
+
−     * Get the next row in the table if there are more.
+
−     *
+
−     * @return A boolean indicating if there are more rows to fetch
+
−     */
+
−    protected boolean tryContinueIteration() {
+
−        if(this.hasMore()) {
+
−            this.currentIterationNumber++;
+
−            return true;
+
−        }
+
−        return false;
+
−    }
+
−}