org.apache.torque.om

## Class ComboKey

- java.lang.Object
- - org.apache.torque.om.ObjectKey<SimpleKey<?>[]>
  - - org.apache.torque.om.ComboKey

- All Implemented Interfaces:
    Serializable, Comparable<Object>

      public class ComboKey
      extends ObjectKey<SimpleKey<?>[]>

  This class can be used as an ObjectKey to uniquely identify an object within an application where the key consists of multiple entities (such a String[] representing a multi-column primary key).
  Version:
    $Id: ComboKey.java 1879896 2020-07-15 15:03:46Z gk $
  Author:
    John McNally, Daniel Rall, J. Russell Smyth
  See Also:
    Serialized Form

- - ### Field Summary

    Fields
    Modifier and Type | Field and Description
    --- | ---
    `static char` | `SEPARATOR` The single character used to separate key values in a string.
    `static String` | `SEPARATOR_STRING` The single character used to separate key values in a string.

  - ### Constructor Summary

    Constructors
    Constructor and Description
    `ComboKey()` Initializes the internal key value to `null`.
    `ComboKey(ComboKey key)` Creates a ComboKey that is equivalent to key.
    `ComboKey(SimpleKey<?>[] key)` Creates an ComboKey and set its internal representation
    `ComboKey(String key)` Creates an ComboKey and set its internal representation

  - ### Method Summary

    All Methods Instance Methods Concrete Methods
    Modifier and Type | Method and Description
    --- | ---
    `void` | `appendTo(StringBuilder sb)` Appends a String representation of the key to a buffer.
    `boolean` | `equals(Object keyObj)` This method will return true if the conditions for a looseEquals are met and in addition no parts of the keys are null.
    `int` | `getJdbcType()` Returns the JDBC type of the key as defined in `java.sql.Types`.
    `int` | `hashCode()` if the underlying key array is not null and the first element is not null this method returns the hashcode of the first element in the key.
    `boolean` | `looseEquals(Object keyObj)` keyObj is equal to this ComboKey if keyObj is a ComboKey, String, ObjectKey[], or String[] that contains the same information this key contains.
    `void` | `setValue(String keys)` Sets the internal representation using a String of the form produced by the toString method.
    `String` | `toString()` A String that may consist of one section or multiple sections separated by a colon.

    - ### Methods inherited from class org.apache.torque.om.ObjectKey

      `compareTo, getValue, setValue, setValue`

    - ### Methods inherited from class java.lang.Object

      `clone, finalize, getClass, notify, notifyAll, wait, wait, wait`

- - ### Field Detail

    - #### SEPARATOR

          public static final char SEPARATOR

      The single character used to separate key values in a string.
      See Also:
        Constant Field Values

    - #### SEPARATOR_STRING

          public static final String SEPARATOR_STRING

      The single character used to separate key values in a string.
      See Also:
        Constant Field Values

  - ### Constructor Detail

    - #### ComboKey

          public ComboKey()

      Initializes the internal key value to `null`.

    - #### ComboKey

          public ComboKey(String key)

      Creates an ComboKey and set its internal representation
      Parameters:
        `key` - the key value as String

    - #### ComboKey

          public ComboKey(SimpleKey<?>[] key)

      Creates an ComboKey and set its internal representation
      Parameters:
        `key` - the key value

    - #### ComboKey

          public ComboKey(ComboKey key)

      Creates a ComboKey that is equivalent to key.
      Parameters:
        `key` - the key value

  - ### Method Detail

    - #### setValue

          public void setValue(String keys)

      Sets the internal representation using a String of the form produced by the toString method.
      Parameters:
        `keys` - the key values

    - #### getJdbcType

          public int getJdbcType()

      Returns the JDBC type of the key as defined in `java.sql.Types`.
      Specified by:
        `getJdbcType` in class `ObjectKey<SimpleKey<?>[]>`
      Returns:
        `Types.ARRAY`.

    - #### equals

          public boolean equals(Object keyObj)

      This method will return true if the conditions for a looseEquals are met and in addition no parts of the keys are null.
      Overrides:
        `equals` in class `ObjectKey<SimpleKey<?>[]>`
      Parameters:
        `keyObj` - the comparison value
      Returns:
        whether the two objects are equal

    - #### looseEquals

          public boolean looseEquals(Object keyObj)

      keyObj is equal to this ComboKey if keyObj is a ComboKey, String, ObjectKey[], or String[] that contains the same information this key contains. For example A String[] might be equal to this key, if this key was instantiated with a String[] and the arrays contain equal Strings. Another example, would be if keyObj is an ComboKey that was instantiated with a ObjectKey[] and this ComboKey was instantiated with a String[], but the ObjectKeys in the ObjectKey[] were instantiated with Strings that equal the Strings in this KeyObject's String[] This method is not as strict as the equals method which does not allow any null keys parts, while the internal key may not be null portions may be, and the two object will be considered equal if their null portions match.
      Parameters:
        `keyObj` - the comparison value
      Returns:
        whether the two objects are equal

    - #### appendTo

          public void appendTo(StringBuilder sb)

      Description copied from class: `ObjectKey`
      Appends a String representation of the key to a buffer.
      Overrides:
        `appendTo` in class `ObjectKey<SimpleKey<?>[]>`
      Parameters:
        `sb` - the StringBuilder to append
      See Also:
        `toString()`

    - #### hashCode

          public int hashCode()

      if the underlying key array is not null and the first element is not null this method returns the hashcode of the first element in the key. Otherwise calls ObjectKey.hashCode()
      Overrides:
        `hashCode` in class `ObjectKey<SimpleKey<?>[]>`
      Returns:
        an `int` value

    - #### toString

          public String toString()

      A String that may consist of one section or multiple sections separated by a colon.

      Each Key is represented by `[type N|S|D][value][:]`.

      Example:

      the ComboKey(StringKey("key1"), NumberKey(2)) is represented as `Skey1:N2:`

      Overrides:
        `toString` in class `ObjectKey<SimpleKey<?>[]>`
      Returns:
        a String representation

Copyright © 2000–2020 The Apache Software Foundation. All rights reserved.