Class ObjectKey<T>

java.lang.Object
org.apache.torque.om.ObjectKey<T>
All Implemented Interfaces:
Serializable, Comparable<Object>
Direct Known Subclasses:
ComboKey, SimpleKey

public abstract class ObjectKey<T> extends Object implements Serializable, Comparable<Object>
This class can be used to uniquely identify an object within an application. There are four subclasses: StringKey, NumberKey, and DateKey, and ComboKey which is a Key made up of a combination of the first three.
Version:
$Id: ObjectKey.java 1917245 2024-04-21 14:06:23Z tv $
Author:
John McNally
See Also:
  • Constructor Summary

    Constructors
    Constructor
    Description
    Initializes the internal key value to null.
  • Method Summary

    Modifier and Type
    Method
    Description
    void
    Appends a String representation of the key to a buffer.
    int
    Implements the compareTo method.
    boolean
    Returns whether this ObjekctKey is equal to another Object.
    abstract int
    Returns the JDBC type of the key as defined in java.sql.Types.
    Get the underlying object.
    int
    Returns the hashcode of the underlying value (key), if key is not null.
    <O extends ObjectKey<T>>
    void
    setValue(O key)
    Sets the internal representation to the same object used by key.
    void
    setValue(T key)
    Sets the internal representation.
    Get a String representation of this key.

    Methods inherited from class java.lang.Object

    clone, finalize, getClass, notify, notifyAll, wait, wait, wait
  • Constructor Details

    • ObjectKey

      public ObjectKey()
      Initializes the internal key value to null.
  • Method Details

    • hashCode

      public int hashCode()
      Returns the hashcode of the underlying value (key), if key is not null. Otherwise calls Object.hashCode()
      Overrides:
      hashCode in class Object
      Returns:
      an int value
    • equals

      public boolean equals(Object obj)
      Returns whether this ObjekctKey is equal to another Object. obj is equal to this ObjectKey if obj has the same class as this ObjectKey and contains the same information this key contains. Two ObjectKeys that both contain null values are not considered equal.
      Overrides:
      equals in class Object
      Parameters:
      obj - the comparison value.
      Returns:
      whether the two objects are equal.
    • getValue

      public T getValue()
      Get the underlying object.
      Returns:
      the underlying object
    • getJdbcType

      public abstract int getJdbcType()
      Returns the JDBC type of the key as defined in java.sql.Types.
      Returns:
      the JDBC type of the key.
    • appendTo

      public void appendTo(StringBuilder sb)
      Appends a String representation of the key to a buffer.
      Parameters:
      sb - a StringBuilder
    • compareTo

      public int compareTo(Object obj)
      Implements the compareTo method.
      Specified by:
      compareTo in interface Comparable<T>
      Parameters:
      obj - the object to compare to this object
      Returns:
      a numeric comparison of the two values
    • setValue

      public void setValue(T key)
      Sets the internal representation.
      Parameters:
      key - the key value
    • setValue

      public <O extends ObjectKey<T>> void setValue(O key)
      Sets the internal representation to the same object used by key.
      Type Parameters:
      O - the key type
      Parameters:
      key - the key value
    • toString

      public String toString()
      Get a String representation of this key.
      Overrides:
      toString in class Object
      Returns:
      a String representation of this key, or an empty String if the value is null.