Package com.yahoo.prelude.query

Class NotItem

  • All Implemented Interfaces:
    Cloneable
    public class NotItem
extends CompositeItem
    A composite item where the first item is positive and the following items are negative items where matches should exclude the document should from the result. The default positive item, if only negatives are added, is TrueItem: Meaning that all documents are matched except those matching the negative terms added.
    Author:
    bratseth

    • Constructor Detail

      • NotItem

        public NotItem()

    • Method Detail

      • 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 String getName()
        Description copied from class: Item
        Returns the name of this item
        Specified by:
        getName in class Item

      • addItem

        public void addItem​(Item item)
        Adds an item. The first item is the positive, the rest are negative
        Overrides:
        addItem in class CompositeItem

      • addNegativeItem

        public void addNegativeItem​(Item negative)
        Adds a negative item. Like addItem but skips the first position (position 0) if it is not already set.

      • negativeItems

        public List<Item> negativeItems()
        Returns the negative items of this: All child items except the first

      • getPositiveItem

        public Item getPositiveItem()
        Returns the positive item (the first subitem), or TrueItem if no positive items has been added.

      • setPositiveItem

        public Item setPositiveItem​(Item item)
        Sets the positive item (the first item)
        Returns:
        the old positive item, or TrueItem if there was none

      • addPositiveItem

        public void addPositiveItem​(Item item)
        Convenience method for adding a positive item. If a positive item is already present the positive item becomes an AndItem with the items added

      • removeItem

        public boolean removeItem​(Item item)
        Description copied from class: CompositeItem
        Removes the given item. Does nothing if the item is not present.
        Overrides:
        removeItem in class CompositeItem
        Parameters:
        item - the item to remove
        Returns:
        whether the item was removed

      • removeItem

        public Item removeItem​(int index)
        Description copied from class: CompositeItem
        Removes the item at the given index
        Overrides:
        removeItem in class CompositeItem
        Parameters:
        index - the index of the item to remove
        Returns:
        the removed item

      • appendHeadingString

        protected void appendHeadingString​(StringBuilder buffer)
        Not items uses a empty heading instead of "NOT "
        Overrides:
        appendHeadingString in class Item

      • appendBodyString

        protected void appendBodyString​(StringBuilder buffer)
        Overridden to skip the positive TrueItem and (otherwise) append "+" to the first item and "-" to the rest
        Overrides:
        appendBodyString in class CompositeItem

      • getTermCount

        public int getTermCount()
        Returns the number of actual *positive* terms in this
        Overrides:
        getTermCount in class CompositeItem