org.cip4.jdflib.util
Class HashUtil

java.lang.Object
  org.cip4.jdflib.util.HashUtil

public class HashUtil
extends Object

This class provides some hashCode calculation utilities. Use the static methods of this class to generate

 hashCode()
 

values in data objects. For example, to calculate the hashCode of a data object, use the methods of this class as follows:

 int myIntField;
 Object myObject;
 
 public int hashCode()
 {
        //        int hash = super.hashCode();    // use when not extending Object
        int hash = 0; // use when extending Object
        hash = HashUtil.hashCode(hash, myIntField);
        hash = HashUtil.hashCode(hash, myObject);
        return hash;
 }
 

Hint: Start your hashCode calculation depending on the object your data object extends. If you extend Object initialize your hash value to 0. Otherwise initialize hash to super.hashCode(). See the example code.

Author:

Manfred Steinbach

Field Summary

static int

PRIME

Method Summary

static int	hashCode(int source, boolean x)
static int	hashCode(int source, Collection<?> c)
static int	hashCode(int source, double x)
static int	hashCode(int source, float x)
static int	hashCode(int source, int x)
static int	hashCode(int source, long x)
static int	hashCode(int source, Object x)
static int	hashCode(int source, Object[] x)

Methods inherited from class java.lang.Object

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

Field Detail

PRIME

public static final int PRIME

See Also:

Constant Field Values

Method Detail

hashCode

public static final int hashCode(int source,
                                 boolean x)

Parameters:

source -

x -

Returns:

hashCode

public static final int hashCode(int source,
                                 int x)

Parameters:

source -

x -

Returns:

hashCode

public static final int hashCode(int source,
                                 long x)

Parameters:

source -

x -

Returns:

hashCode

public static final int hashCode(int source,
                                 float x)

Parameters:

source -

x -

Returns:

hashCode

public static final int hashCode(int source,
                                 double x)

Parameters:

source -

x -

Returns:

hashCode

public static final int hashCode(int source,
                                 Object x)

Parameters:

source -

x -

Returns:

hashCode

public static final int hashCode(int source,
                                 Collection<?> c)

Parameters:

source -

c -

Returns:

hashCode

public static final int hashCode(int source,
                                 Object[] x)

Parameters:

source -

x -

Returns: