com.imagero.gui.swing.tree.util
Class DMNodeComparator

java.lang.Object
  com.imagero.gui.swing.tree.util.DMNodeComparator

All Implemented Interfaces:

java.util.Comparator, TreeNodeComparator

Direct Known Subclasses:

FileNodeComparator, HTTPNodeComparator, URLNodeComparator

public class DMNodeComparator

extends java.lang.Object

implements TreeNodeComparator

since this comparator knows nothing about userObjects in nodes, it makes only simple check for null values and (if needed) directory check. subclasses should call super.compare() and if result is UNDEFINED make further comparison

Field Summary

protected boolean	directoriesFirst
static int	UNDEFINED

Constructor Summary

DMNodeComparator()

Method Summary

protected int	checkDirectory(javax.swing.tree.TreeNode tn1, javax.swing.tree.TreeNode tn2) check if some of nodes is directory
protected int	checkNull(javax.swing.tree.TreeNode tn1, javax.swing.tree.TreeNode tn2) check null nodes
int	compare(HTreeNode tn1, HTreeNode tn2)
int	compare(java.lang.Object o1, java.lang.Object o2) Compares its two arguments for order.
boolean	equals(java.lang.Object o) Indicates whether some other object is "equal to" this Comparator.
boolean	isDirectoriesFirst()
void	setDirectoriesFirst(boolean b)

Methods inherited from class java.lang.Object

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

Field Detail

directoriesFirst

protected boolean directoriesFirst

UNDEFINED

public static final int UNDEFINED

See Also:

Constant Field Values

Constructor Detail

DMNodeComparator

public DMNodeComparator()

Method Detail

checkDirectory

protected int checkDirectory(javax.swing.tree.TreeNode tn1,
                             javax.swing.tree.TreeNode tn2)

check if some of nodes is directory

Parameters:

tn1 - first node

tn2 - second node

Returns:

-1 if first node is directory and second node is not directory, 1 if first node is not directory and second node node is directory, UNDEFINED if both nodes are directories or not;

checkNull

protected int checkNull(javax.swing.tree.TreeNode tn1,
                        javax.swing.tree.TreeNode tn2)

check null nodes

Parameters:

tn1 - first node

tn2 - second node

Returns:

0 if both nodes are null, 1 if first node is not null and second node is null, -1 if fist node is null and second node is not null, -2 id both nodes are not null;

compare

public int compare(HTreeNode tn1,
                   HTreeNode tn2)

Specified by:

compare in interface TreeNodeComparator

Parameters:

tn1 - first node

tn2 - second node

Returns:

UNDEFINED if compare result is unknown

compare

public int compare(java.lang.Object o1,
                   java.lang.Object o2)

Description copied from interface: java.util.Comparator

Compares its two arguments for order. Returns a negative integer, zero, or a positive integer as the first argument is less than, equal to, or greater than the second.

The implementor must ensure that sgn(compare(x, y)) == -sgn(compare(y, x)) for all x and y. (This implies that compare(x, y) must throw an exception if and only if compare(y, x) throws an exception.)

The implementor must also ensure that the relation is transitive: ((compare(x, y)>0) && (compare(y, z)>0)) implies compare(x, z)>0.

Finally, the implementer must ensure that compare(x, y)==0 implies that sgn(compare(x, z))==sgn(compare(y, z)) for all z.

It is generally the case, but not strictly required that (compare(x, y)==0) == (x.equals(y)). Generally speaking, any comparator that violates this condition should clearly indicate this fact. The recommended language is "Note: this comparator imposes orderings that are inconsistent with equals."

Specified by:

compare in interface java.util.Comparator

Parameters:

o1 - the first object to be compared.

o2 - the second object to be compared.

Returns:

a negative integer, zero, or a positive integer as the first argument is less than, equal to, or greater than the second.

equals

public boolean equals(java.lang.Object o)

Description copied from interface: java.util.Comparator

Indicates whether some other object is "equal to" this Comparator. This method must obey the general contract of Object.equals(Object). Additionally, this method can return true only if the specified Object is also a comparator and it imposes the same ordering as this comparator. Thus, comp1.equals(comp2) implies that sgn(comp1.compare(o1, o2))==sgn(comp2.compare(o1, o2)) for every object reference o1 and o2.

Note that it is always safe not to override Object.equals(Object). However, overriding this method may, in some cases, improve performance by allowing programs to determine that two distinct Comparators impose the same order.

Specified by:

equals in interface java.util.Comparator

Parameters:

o - the reference object with which to compare.

Returns:

true if this object is the same as the obj argument; false otherwise.

See Also:

Object.hashCode(), Hashtable

isDirectoriesFirst

public boolean isDirectoriesFirst()

setDirectoriesFirst

public void setDirectoriesFirst(boolean b)