Package com.groiss.ds

Class ListComparator

java.lang.Object

com.groiss.ds.ListComparator

All Implemented Interfaces:

Serializable, Comparator<List<Object>>

public class ListComparator
extends Object
implements Comparator<List<Object>>, Serializable

Compare two lists. This class is used for sorting tables, where each table row is a list.

See Also:

• Serialized Form

Constructor Summary

Constructors

Constructor	Description
ListComparator(int[] sortcols)	Construct a list comparator with an array of sort columns.
ListComparator(int column, boolean ascending)	Construct a list comparator with a sort column and a boolean for sort direction.
ListComparator(int column, boolean ascending, int column2, boolean ascending2)	Construct a list comparator with two sort columns and booleans for sort direction.

Method Summary

Modifier and Type	Method	Description
int	compare(List<Object> o1, List<Object> o2)	Compare two lists.
static int	compareNumbers(Number n1, Number n2)	Compares 2 Objects implementing Interface Number, even if they are different types
static int	compareObjects(Object first, Object second)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface java.util.Comparator

equals, reversed, thenComparing, thenComparing, thenComparing, thenComparingDouble, thenComparingInt, thenComparingLong

Constructor Details

ListComparator

public ListComparator(int column,
 boolean ascending)

Construct a list comparator with a sort column and a boolean for sort direction.

Parameters:

column - sort column

ascending - true if sort ascending

ListComparator

public ListComparator(int column,
 boolean ascending,
 int column2,
 boolean ascending2)

Construct a list comparator with two sort columns and booleans for sort direction.

Parameters:

column - sort column

ascending - true if sort ascending

column2 - sort column2

ascending2 - true if sort column2 ascending

ListComparator

public ListComparator(int[] sortcols)

Construct a list comparator with an array of sort columns. Positive integers are used for sorting ascending, negative for sorting descending. The column numbers start with 1.
Example: the argument [-1,2] sorts first the colum with index zero descending, then the first column (index one in list) ascending.

Parameters:

sortcols - array of sort columns

Method Details

compare

public int compare(List<Object> o1,
 List<Object> o2)

Compare two lists.

Specified by:

compare in interface Comparator<List<Object>>

compareObjects

public static int compareObjects(Object first,
 Object second)

compareNumbers

public static int compareNumbers(Number n1,
 Number n2)

Compares 2 Objects implementing Interface Number, even if they are different types