Class EmptyTupleSequence

  • All Implemented Interfaces:
    Tuple, TupleSequence

    public class EmptyTupleSequence
    extends java.lang.Object
    implements TupleSequence
    TupleSequence implementation with no data. The next method always returns false.
    Since:
    19 Dec 2018
    Author:
    Mark Taylor
    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      boolean getBooleanValue​(int ic)
      Returns the value of a given column as a boolean.
      double getDoubleValue​(int ic)
      Returns the value of a given column as a double.
      int getIntValue​(int ic)
      Returns the value of a given column as an integer.
      long getLongValue​(int ic)
      Returns the value of a given column as a long.
      java.lang.Object getObjectValue​(int ic)
      Returns the value of a given column as an object.
      long getRowIndex()
      Returns the row index for the underlying data set.
      boolean next()
      Move to the next item in the sequence.
      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
    • Constructor Detail

      • EmptyTupleSequence

        public EmptyTupleSequence()
    • Method Detail

      • next

        public boolean next()
        Description copied from interface: TupleSequence
        Move to the next item in the sequence. Must be called before accessing each row, including the first one. Returns false when there are no rows left.
        Specified by:
        next in interface TupleSequence
        Returns:
        true iff the item moved to has data
      • getBooleanValue

        public boolean getBooleanValue​(int ic)
        Description copied from interface: Tuple
        Returns the value of a given column as a boolean. If that element of the table is not of boolean type, the result may not be useful.
        Specified by:
        getBooleanValue in interface Tuple
        Parameters:
        ic - column index
        Returns:
        value of element icol, presumed of boolean type
      • getIntValue

        public int getIntValue​(int ic)
        Description copied from interface: Tuple
        Returns the value of a given column as an integer. If that element of the tuple is not of numeric type, the result may not be useful.
        Specified by:
        getIntValue in interface Tuple
        Parameters:
        ic - column index
        Returns:
        value of element icol, presumed of numeric type
      • getLongValue

        public long getLongValue​(int ic)
        Description copied from interface: Tuple
        Returns the value of a given column as a long. If that element of the tuple is not of numeric type, the result may not be useful.
        Specified by:
        getLongValue in interface Tuple
        Parameters:
        ic - column index
        Returns:
        value of element icol, presumed of numeric type
      • getDoubleValue

        public double getDoubleValue​(int ic)
        Description copied from interface: Tuple
        Returns the value of a given column as a double. If that element of the tuple is not of numeric type, the result may not be useful.
        Specified by:
        getDoubleValue in interface Tuple
        Parameters:
        ic - column index
        Returns:
        value of element icol, presumed of numeric type
      • getObjectValue

        public java.lang.Object getObjectValue​(int ic)
        Description copied from interface: Tuple
        Returns the value of a given column as an object. If that element of the tuple is not of object type, the result may not be useful.

        If the result is a mutable object, its value may be overwritten by subsequent calls to this method (especially following calls to TupleSequence.next() if this object also implements TupleSequence).

        Specified by:
        getObjectValue in interface Tuple
        Parameters:
        ic - column index
        Returns:
        value of element icol, presumed of object type
      • getRowIndex

        public long getRowIndex()
        Description copied from interface: Tuple
        Returns the row index for the underlying data set. Note this value may not undergo a simple increment between steps (if rows are excluded from the underlying data set it may increase by more than one in some cases).
        Specified by:
        getRowIndex in interface Tuple
        Returns:
        row index of underlying table row