Package com.yahoo.search.query

Class QueryTree

  • All Implemented Interfaces:
    java.lang.Cloneable
    public class QueryTree
extends CompositeItem
    The root node of a query tree. This is always present above the actual semantic root to ease query manipulation, especially replacing the actual semantic root, but does not have any search semantics on its own.

    To ease recursive manipulation of the query tree, this is a composite having one child, which is the actual root.

    • Setting the root item (at position 0, either directly or though the iterator of this, works as expected. Setting at any other position is disallowed.
    • Removing the root is allowed and causes this to be a null query.
    • Adding an item is only allowed if this is currently a null query (having no root)

    This is also the home of accessor methods which eases querying into and manipulation of the query tree.

    Author:
    Arne Bergene Fossaa

    • Constructor Detail

      • QueryTree

        public QueryTree​(Item root)

    • Method Detail

      • setIndexName

        public void setIndexName​(java.lang.String index)
        Description copied from class: CompositeItem
        Sets the index name of all subitems of this
        Overrides:
        setIndexName in class CompositeItem

      • getItemType

        public Item.ItemType getItemType()
        Description copied from class: Item
        Return the enumerated type of this item.
        Specified by:
        getItemType in class Item

      • getName

        public java.lang.String getName()
        Description copied from class: Item
        Returns the name of this item
        Specified by:
        getName in class Item

      • encode

        public int encode​(java.nio.ByteBuffer buffer)
        Overrides:
        encode in class CompositeItem

      • appendHeadingString

        protected void appendHeadingString​(java.lang.StringBuilder sb)
        Description copied from class: Item
        Appends the heading of this string. As default getName() followed by a space.
        Overrides:
        appendHeadingString in class Item

      • getRoot

        public Item getRoot()
        Returns the query root. This is null if this is a null query.

      • setRoot

        public final void setRoot​(Item root)

      • equals

        public boolean equals​(java.lang.Object o)
        Description copied from class: CompositeItem
        Returns whether this item is of the same class and contains the same state as the given item
        Overrides:
        equals in class CompositeItem

      • addItem

        public void addItem​(int index,
                    Item item)
        Description copied from class: CompositeItem
        Inserts the item at a position and increases the index of existing items starting on this position by one
        Overrides:
        addItem in class CompositeItem

      • isEmpty

        public boolean isEmpty()
        Returns true if this represents the null query

      • and

        public Item and​(Item item)
        Modifies this query to become the current query AND the given item.
        Returns:
        the resulting root item in this

      • getPositiveTerms

        public static java.util.List<IndexedItem> getPositiveTerms​(Item item)
        Returns a flattened list of all positive query terms under the given item