How to use

removeFromParent

method

in

org.modeshape.jcr.query.plan.PlanNode

/**
 * Add the supplied node to the end of the list of children.
 *
 * @param child the node that should be added as the last child; may not be null
 */
public void addLastChild( PlanNode child ) {
  assert child != null;
  this.children.addLast(child);
  child.removeFromParent();
  child.parent = this;
}

/**
 * Add the supplied node to the front of the list of children.
 *
 * @param child the node that should be added as the first child; may not be null
 */
public void addFirstChild( PlanNode child ) {
  assert child != null;
  this.children.addFirst(child);
  child.removeFromParent();
  child.parent = this;
}

/**
 * Add the supplied node to the end of the list of children.
 *
 * @param child the node that should be added as the last child; may not be null
 */
public void addLastChild( PlanNode child ) {
  assert child != null;
  this.children.addLast(child);
  child.removeFromParent();
  child.parent = this;
}

/**
 * Add the supplied node to the front of the list of children.
 *
 * @param child the node that should be added as the first child; may not be null
 */
public void addFirstChild( PlanNode child ) {
  assert child != null;
  this.children.addFirst(child);
  child.removeFromParent();
  child.parent = this;
}

/**
 * Set the parent for this node. If this node already has a parent, this method will remove this node from the current parent.
 * If the supplied parent is not null, then this node will be added to the supplied parent's children.
 *
 * @param parent the new parent, or null if this node is to have no parent
 */
public void setParent( PlanNode parent ) {
  removeFromParent();
  if (parent != null) {
    this.parent = parent;
    this.parent.children.add(this);
  }
}

/**
 * Set the parent for this node. If this node already has a parent, this method will remove this node from the current parent.
 * If the supplied parent is not null, then this node will be added to the supplied parent's children.
 *
 * @param parent the new parent, or null if this node is to have no parent
 */
public void setParent( PlanNode parent ) {
  removeFromParent();
  if (parent != null) {
    this.parent = parent;
    this.parent.children.add(this);
  }
}

/**
 * Replace the supplied child with another node. If the replacement is already a child of this node, this method effectively
 * swaps the position of the child and replacement nodes.
 *
 * @param child the node that is already a child and that is to be replaced; may not be null and must be a child
 * @param replacement the node that is to replace the 'child' node; may not be null
 * @return true if the child was successfully replaced
 */
public boolean replaceChild( PlanNode child,
               PlanNode replacement ) {
  assert child != null;
  assert replacement != null;
  if (child.parent == this) {
    int i = this.children.indexOf(child);
    if (replacement.parent == this) {
      // Swapping the positions ...
      int j = this.children.indexOf(replacement);
      this.children.set(i, replacement);
      this.children.set(j, child);
      return true;
    }
    // The replacement is not yet a child ...
    this.children.set(i, replacement);
    replacement.removeFromParent();
    replacement.parent = this;
    child.parent = null;
    return true;
  }
  return false;
}

/**
 * Replace the supplied child with another node. If the replacement is already a child of this node, this method effectively
 * swaps the position of the child and replacement nodes.
 *
 * @param child the node that is already a child and that is to be replaced; may not be null and must be a child
 * @param replacement the node that is to replace the 'child' node; may not be null
 * @return true if the child was successfully replaced
 */
public boolean replaceChild( PlanNode child,
               PlanNode replacement ) {
  assert child != null;
  assert replacement != null;
  if (child.parent == this) {
    int i = this.children.indexOf(child);
    if (replacement.parent == this) {
      // Swapping the positions ...
      int j = this.children.indexOf(replacement);
      this.children.set(i, replacement);
      this.children.set(j, child);
      return true;
    }
    // The replacement is not yet a child ...
    this.children.set(i, replacement);
    replacement.removeFromParent();
    replacement.parent = this;
    child.parent = null;
    return true;
  }
  return false;
}

newParent.removeFromParent();
if (this.parent != null) {
  this.parent.replaceChild(this, newParent);

newParent.removeFromParent();
if (this.parent != null) {
  this.parent.replaceChild(this, newParent);

@Override
public PlanNode execute( QueryContext context,
             PlanNode plan,
             LinkedList<OptimizerRule> ruleStack ) {
  // For each of the JOIN nodes ...
  for (PlanNode joinNode : plan.findAllAtOrBelow(Type.JOIN)) {
    if (JoinType.RIGHT_OUTER == joinNode.getProperty(Property.JOIN_TYPE, JoinType.class)) {
      // Swap the information ...
      PlanNode left = joinNode.getFirstChild();
      left.removeFromParent(); // right is now the first child ...
      left.setParent(joinNode);
      joinNode.setProperty(Property.JOIN_TYPE, JoinType.LEFT_OUTER);
      // None of the Constraints or JoinCondition need to be changed (they refer to named selectors) ...
    }
  }
  return plan;
}

@Override
public PlanNode execute( QueryContext context,
             PlanNode plan,
             LinkedList<OptimizerRule> ruleStack ) {
  // For each of the JOIN nodes ...
  for (PlanNode joinNode : plan.findAllAtOrBelow(Type.JOIN)) {
    if (JoinType.RIGHT_OUTER == joinNode.getProperty(Property.JOIN_TYPE, JoinType.class)) {
      // Swap the information ...
      PlanNode left = joinNode.getFirstChild();
      left.removeFromParent(); // right is now the first child ...
      left.setParent(joinNode);
      joinNode.setProperty(Property.JOIN_TYPE, JoinType.LEFT_OUTER);
      // None of the Constraints or JoinCondition need to be changed (they refer to named selectors) ...
    }
  }
  return plan;
}

@Test
public void shouldRemoveFromParentWhenThereIsNoParent() {
  node = new PlanNode(Type.JOIN);
  PlanNode child1 = new PlanNode(Type.ACCESS, node);
  assertThat(node.getFirstChild(), is(sameInstance(child1)));
  assertThat(node.getChildCount(), is(1));
  // Perform the removeFromParent ...
  assertThat(node.removeFromParent(), is(nullValue()));
  assertThat(node.getFirstChild(), is(sameInstance(child1)));
  assertThat(node.getChildCount(), is(1));
}

if (swapChildren) {
  PlanNode first = join.getFirstChild();
  first.removeFromParent();
  join.addLastChild(first);
  if (joinType == JoinType.LEFT_OUTER){

if (swapChildren) {
  PlanNode first = join.getFirstChild();
  first.removeFromParent();
  join.addLastChild(first);
  if (joinType == JoinType.LEFT_OUTER){

@Test
public void shouldRemoveFromParentWhenThereIsAParent() {
  parent = new PlanNode(Type.JOIN);
  PlanNode child1 = new PlanNode(Type.ACCESS, parent);
  PlanNode child2 = new PlanNode(Type.DUP_REMOVE, parent);
  PlanNode child3 = new PlanNode(Type.GROUP, parent);
  PlanNode grandChild21 = new PlanNode(Type.LIMIT, child2);
  assertThat(parent.getFirstChild(), is(sameInstance(child1)));
  assertThat(parent.getChild(1), is(sameInstance(child2)));
  assertThat(parent.getLastChild(), is(sameInstance(child3)));
  assertThat(parent.getChildCount(), is(3));
  assertThat(child2.getFirstChild(), is(sameInstance(grandChild21)));
  // Perform the removeFromParent ...
  assertThat(child2.removeFromParent(), is(sameInstance(parent)));
  assertThat(parent.getFirstChild(), is(sameInstance(child1)));
  assertThat(parent.getLastChild(), is(sameInstance(child3)));
  assertThat(parent.getChildCount(), is(2));
  // There should still be the child in the removed node ...
  assertThat(child2.getFirstChild(), is(sameInstance(grandChild21)));
}

assert sort.getParent() == distinct;
sort.removeFromParent();
assert sort.getParent() == null;

assert sort.getParent() == distinct;
sort.removeFromParent();
assert sort.getParent() == null;

  access.removeFromParent();
} else {
  project.extractFromParent();

  access.removeFromParent();
} else {
  project.extractFromParent();