+
−package nl.cwi.monetdb.embedded.tables;
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−
+
−import nl.cwi.monetdb.embedded.mapping.MonetDBToJavaMapping;
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−
+
−/**
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− * 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>
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− */
+
−public class RowIterator {
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−
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−    /**
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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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−    /**
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−     * The mappings of the currentColumns.
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−     */
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−    protected final MonetDBToJavaMapping[] mappings;
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−
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−    /**
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−     * The currentColumns values as Java objects.
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−     */
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−    protected Object[] currentColumns;
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−
+
−    /**
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−     * The current row number.
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−     */
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−    protected int currentRowNumber;
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−
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−    /**
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−     * The first row in the table to iterate.
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−     */
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−    protected final int firstIndex;
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−
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−    /**
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−     * The last row in the table to iterate.
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−     */
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−    protected final int lastIndex;
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−
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−    public RowIterator(MonetDBTable table, int firstIndex, int lastIndex) {
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−        this.table = table;
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−        this.mappings = table.getMappings();
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−        this.firstIndex = Math.max(firstIndex, 0);
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−        this.lastIndex = Math.min(Math.min(lastIndex, table.getNumberOfRows()), 0);
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−        this.currentRowNumber = this.firstIndex - 1; //starting on the row before the first index
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−    }
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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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−
+
−    /**
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−     * 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
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−     */
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−    public Object[] getCurrentColumns() { return currentColumns; }
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−
+
−    /**
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−     * Gets the current row number in the iteration.
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−     *
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−     * @return The current row number in the iteration
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−     */
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−    public int getCurrentRowNumber() { return currentRowNumber; }
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−
+
−    /**
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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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−
+
−    /**
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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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−     */
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−    public int getLastIndex() { return lastIndex; }
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−
+
−    /**
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−     * 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
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−     */
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−    public boolean hasMore() { return currentRowNumber < lastIndex; }
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−
+
−    /**
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−     * 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 getColumn(int index, Class<T> javaClass) { return javaClass.cast(this.currentColumns[index]); }
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−
+
−    /**
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−     * 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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−     */
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−    public <T> T getColumn(int index) {
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−        Class<T> javaClass = this.mappings[index].getJavaClass();
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−        return javaClass.cast(this.currentColumns[index]);
+
−    }
+
−
+
−    /**
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−     * Method used by JNI to set the next columns and increment the current row number.
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−     *
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−     * @param columns The next retrieved columns
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−     */
+
−    protected void setNextIteration(Object[] columns) {
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−        this.currentColumns = columns;
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−        this.currentRowNumber++;
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−    }
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−
+
−    /**
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−     * Gets the next row in the iteration if there are more.
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−     *
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−     * @return A boolean indicating if a row was fetched
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−     */
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−    protected native boolean getNextTableRow();
+
−}