Examples with Page org.h2.mvstore.Page used on opensource projects

Example 51 with Page

use of org.h2.mvstore.Page in project h2database by h2database.

the class MVRTreeMap method splitQuadratic.

private Page splitQuadratic(Page p, long writeVersion) {
    Page splitA = newPage(p.isLeaf(), writeVersion);
    Page splitB = newPage(p.isLeaf(), writeVersion);
    float largest = Float.MIN_VALUE;
    int ia = 0, ib = 0;
    for (int a = 0; a < p.getKeyCount(); a++) {
        Object objA = p.getKey(a);
        for (int b = 0; b < p.getKeyCount(); b++) {
            if (a == b) {
                continue;
            }
            Object objB = p.getKey(b);
            float area = keyType.getCombinedArea(objA, objB);
            if (area > largest) {
                largest = area;
                ia = a;
                ib = b;
            }
        }
    }
    move(p, splitA, ia);
    if (ia < ib) {
        ib--;
    }
    move(p, splitB, ib);
    Object boundsA = keyType.createBoundingBox(splitA.getKey(0));
    Object boundsB = keyType.createBoundingBox(splitB.getKey(0));
    while (p.getKeyCount() > 0) {
        float diff = 0, bestA = 0, bestB = 0;
        int best = 0;
        for (int i = 0; i < p.getKeyCount(); i++) {
            Object o = p.getKey(i);
            float incA = keyType.getAreaIncrease(boundsA, o);
            float incB = keyType.getAreaIncrease(boundsB, o);
            float d = Math.abs(incA - incB);
            if (d > diff) {
                diff = d;
                bestA = incA;
                bestB = incB;
                best = i;
            }
        }
        if (bestA < bestB) {
            keyType.increaseBounds(boundsA, p.getKey(best));
            move(p, splitA, best);
        } else {
            keyType.increaseBounds(boundsB, p.getKey(best));
            move(p, splitB, best);
        }
    }
    while (splitB.getKeyCount() > 0) {
        move(splitB, p, 0);
    }
    return splitA;
}

Example 52 with Page

use of org.h2.mvstore.Page in project h2database by h2database.

the class MVRTreeMap method splitLinear.

private Page splitLinear(Page p, long writeVersion) {
    ArrayList<Object> keys = New.arrayList();
    for (int i = 0; i < p.getKeyCount(); i++) {
        keys.add(p.getKey(i));
    }
    int[] extremes = keyType.getExtremes(keys);
    if (extremes == null) {
        return splitQuadratic(p, writeVersion);
    }
    Page splitA = newPage(p.isLeaf(), writeVersion);
    Page splitB = newPage(p.isLeaf(), writeVersion);
    move(p, splitA, extremes[0]);
    if (extremes[1] > extremes[0]) {
        extremes[1]--;
    }
    move(p, splitB, extremes[1]);
    Object boundsA = keyType.createBoundingBox(splitA.getKey(0));
    Object boundsB = keyType.createBoundingBox(splitB.getKey(0));
    while (p.getKeyCount() > 0) {
        Object o = p.getKey(0);
        float a = keyType.getAreaIncrease(boundsA, o);
        float b = keyType.getAreaIncrease(boundsB, o);
        if (a < b) {
            keyType.increaseBounds(boundsA, o);
            move(p, splitA, 0);
        } else {
            keyType.increaseBounds(boundsB, o);
            move(p, splitB, 0);
        }
    }
    while (splitB.getKeyCount() > 0) {
        move(splitB, p, 0);
    }
    return splitA;
}

Example 53 with Page

use of org.h2.mvstore.Page in project h2database by h2database.

the class MVRTreeMap method move.

private static void move(Page source, Page target, int sourceIndex) {
    Object k = source.getKey(sourceIndex);
    if (source.isLeaf()) {
        Object v = source.getValue(sourceIndex);
        target.insertLeaf(0, k, v);
    } else {
        Page c = source.getChildPage(sourceIndex);
        target.insertNode(0, k, c);
    }
    source.remove(sourceIndex);
}

Example 54 with Page

use of org.h2.mvstore.Page in project h2database by h2database.

the class MVRTreeMap method add.

private void add(Page p, long writeVersion, Object key, Object value) {
    if (p.isLeaf()) {
        p.insertLeaf(p.getKeyCount(), key, value);
        return;
    }
    // p is a node
    int index = -1;
    for (int i = 0; i < p.getKeyCount(); i++) {
        if (contains(p, i, key)) {
            index = i;
            break;
        }
    }
    if (index < 0) {
        // a new entry, we don't know where to add yet
        float min = Float.MAX_VALUE;
        for (int i = 0; i < p.getKeyCount(); i++) {
            Object k = p.getKey(i);
            float areaIncrease = keyType.getAreaIncrease(k, key);
            if (areaIncrease < min) {
                index = i;
                min = areaIncrease;
            }
        }
    }
    Page c = p.getChildPage(index).copy(writeVersion);
    if (c.getMemory() > store.getPageSplitSize() && c.getKeyCount() > 4) {
        // split on the way down
        Page split = split(c, writeVersion);
        p.setKey(index, getBounds(c));
        p.setChild(index, c);
        p.insertNode(index, getBounds(split), split);
        // now we are not sure where to add
        add(p, writeVersion, key, value);
        return;
    }
    add(c, writeVersion, key, value);
    Object bounds = p.getKey(index);
    keyType.increaseBounds(bounds, key);
    p.setKey(index, bounds);
    p.setChild(index, c);
}

Example 55 with Page

use of org.h2.mvstore.Page in project h2database by h2database.

the class MVRTreeMap method set.

/**
 * Update the value for the given key. The key must exist.
 *
 * @param p the page
 * @param writeVersion the write version
 * @param key the key
 * @param value the new value
 * @return the old value (never null)
 */
private Object set(Page p, long writeVersion, Object key, Object value) {
    if (p.isLeaf()) {
        for (int i = 0; i < p.getKeyCount(); i++) {
            if (keyType.equals(p.getKey(i), key)) {
                p.setKey(i, key);
                return p.setValue(i, value);
            }
        }
    } else {
        for (int i = 0; i < p.getKeyCount(); i++) {
            if (contains(p, i, key)) {
                Page c = p.getChildPage(i);
                if (get(c, key) != null) {
                    c = c.copy(writeVersion);
                    Object result = set(c, writeVersion, key, value);
                    p.setChild(i, c);
                    return result;
                }
            }
        }
    }
    throw DataUtils.newIllegalStateException(DataUtils.ERROR_INTERNAL, "Not found: {0}", key);
}