oracle.jbo
Class Key

java.lang.Object
  |
  +--oracle.jbo.Key

All Implemented Interfaces:

AttributeList, java.lang.Cloneable, java.io.Serializable

public class Key

extends java.lang.Object

implements java.lang.Cloneable, java.io.Serializable, AttributeList

A primary, foreign, or composite row identifier.

Users should not modify keys: JDeveloper treats keys as if they are immutable.

Call getKey() on a row object to get its unique identifier.

Since:

JDeveloper 3.0

See Also:

Serialized Form

Constructor Summary

Key(byte[] keyBytes)
Deprecated. Use Key(String, AttributeDefImpl) instead

Key(java.lang.Object[] keyValues)
Constructs a Key from a set of key values.

Key(java.lang.Object[] keyValues, long sig, java.lang.Object rowHandle)
Internal: em>Applications should not invoke this method.

Key(java.lang.String sString)
Deprecated. Use Key(String, AttributeDefImpl) instead

Key(java.lang.String sString, AttributeDef[] keyAttrs)

Method Summary

boolean	equals(java.lang.Object val) Tests for equality.
java.lang.Object	getAttribute(int index) Gets the value for a selected column.
java.lang.Object	getAttribute(java.lang.String p0) Gets the value of an attribute.
int	getAttributeCount() Counts the number of columns that define the key.
int	getAttributeIndexOf(java.lang.String p0) Gets the index of column identified by name.
java.lang.String[]	getAttributeNames()
java.lang.Object[]	getAttributeValues()
java.lang.Object[]	getKeyValues() Internal: em>Applications should not invoke this method.
java.lang.Object	getRowHandle() Internal: em>Applications should not invoke this method.
long	getSignature() Internal: em>Applications should not invoke this method.
int	hashCode() Generates a hashcode for this key.
boolean	isNull() Checks if this key is null.
static boolean	isNullKeyValues(java.lang.Object[] keyValues) Finds if the key values are null.
void	setAttribute(int p0, java.lang.Object p1) Sets a key value.
void	setAttribute(java.lang.String p0, java.lang.Object p1) Sets the value of a column identified by name.
byte[]	toByteArray() Deprecated. Use toByteArray(boolean bSignature) instead
byte[]	toByteArray(boolean bSignature) Internal: em>Applications should not invoke this method.
java.lang.String	toString() Internal: For debugging only.
java.lang.String	toStringFormat() Deprecated. Use toStringFormat(boolean bSignature) instead
java.lang.String	toStringFormat(boolean bSignature) Converts the Key to a String representation.

Methods inherited from class java.lang.Object

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

Constructor Detail

Key

public Key(java.lang.Object[] keyValues)

Constructs a Key from a set of key values.

A key may be constructed to identify a row or a set of rows. If it is to identify a unique row, the key values must match the row's key attributes exactly.

A partial key (where some key values are null) may be used to locate a set of partially matching rows. This is applicable only for oracle.jbo.RowIterator's findByKey(Key) method. See oracle.jbo.RowIterator.findByKey(Key) for details.

The key values should be ordered as in the defintion for the given row (that of the Entity or the View Object).

Parameters:

keyValues - an array of key values.

Key

public Key(java.lang.Object[] keyValues,
           long sig,
           java.lang.Object rowHandle)

Internal: em>Applications should not invoke this method.

Key

public Key(java.lang.String sString,
AttributeDef[] keyAttrs)
    throws java.lang.Exception

Key

public Key(java.lang.String sString)
    throws java.lang.Exception

Deprecated. Use Key(String, AttributeDefImpl) instead

Initializes the Key object from it's string representation. The String representation must be obtained via the toStringFormat() function.

Key

public Key(byte[] keyBytes)
    throws java.io.IOException,
           java.lang.ClassNotFoundException

Deprecated. Use Key(String, AttributeDefImpl) instead

Internal.

Applications should not invoke this method.

Method Detail

toStringFormat

public java.lang.String toStringFormat(boolean bSignature)

Converts the Key to a String representation. This is useful in that you can later materialize the Key object via it's string constructor. If bSignature is true, adds the Row handle as well as VO signature to the key string so that if a client connects to the same AM instance, the AM could find out the same VO and same Row based on these ids.

getSignature

public long getSignature()

Internal: em>Applications should not invoke this method.

getRowHandle

public java.lang.Object getRowHandle()

Internal: em>Applications should not invoke this method.

equals

public boolean equals(java.lang.Object val)

Tests for equality.

Keys are considered to be equal if they have the same number of columns, and values in each column are equal.

Overrides:

equals in class java.lang.Object

Parameters:

val - a key to be compaired to this.

Returns:

true if val is a key, and is equal to this.

isNullKeyValues

public static boolean isNullKeyValues(java.lang.Object[] keyValues)

Finds if the key values are null.

Returns:

true if keyValues is empty or if all its values are null.

isNull

public boolean isNull()

Checks if this key is null.

Returns:

true if this key's has no values, or if all its values are null.

hashCode

public int hashCode()

Generates a hashcode for this key.

Overrides:

hashCode in class java.lang.Object

Returns:

the hashcode for the key.

toString

public java.lang.String toString()

Internal: For debugging only.

Overrides:

toString in class java.lang.Object

Returns:

a diagnostic string.

toByteArray

public byte[] toByteArray(boolean bSignature)

Internal: em>Applications should not invoke this method.

getKeyValues

public java.lang.Object[] getKeyValues()

Internal: em>Applications should not invoke this method.

getAttributeCount

public int getAttributeCount()

Counts the number of columns that define the key.

Specified by:

getAttributeCount in interface AttributeList

Returns:

the number of columns.

getAttribute

public java.lang.Object getAttribute(int index)

Gets the value for a selected column.

Specified by:

getAttribute in interface AttributeList

Parameters:

index - the position of the column, where the leftmost column has an index of zero.

Returns:

the value of the column.

getAttribute

public java.lang.Object getAttribute(java.lang.String p0)

Gets the value of an attribute.

This method is not implemented by this class. It may be implemented by subclasses to allow names to be used to access attributes.

Specified by:

getAttribute in interface AttributeList

Parameters:

p0 - ignored.

Returns:

the column's value.

Throws:

InvalidOperException - a runtime exception, whenever invoked.

setAttribute

public void setAttribute(int p0,
                         java.lang.Object p1)

Sets a key value.

This method is not implemented by this class. It may be implemented by subclasses.

Specified by:

setAttribute in interface AttributeList

Parameters:

p0 - ignored.

p1 - ignored.

Throws:

InvalidOperException - at runtime, always.

setAttribute

public void setAttribute(java.lang.String p0,
                         java.lang.Object p1)

Sets the value of a column identified by name.

This method is not implemented by this class. It may be implemented by subclasses that allow attributes to be modified, and to be accessed by name.

Specified by:

setAttribute in interface AttributeList

Parameters:

p0 - ignored.

p1 - ignored.

Throws:

InvalidOperException - a runtime exception, whenever invoked.

getAttributeIndexOf

public int getAttributeIndexOf(java.lang.String p0)

Gets the index of column identified by name.

This method is not implemented by this class. It may be implemented by subclasses to allow names to be used to identify attributes.

Specified by:

getAttributeIndexOf in interface AttributeList

Parameters:

p0 - ignored.

Returns:

the column index, where the leftmost column has index zero.

Throws:

InvalidOperException - a runtime exception, whenever invoked.

getAttributeNames

public java.lang.String[] getAttributeNames()

Specified by:

getAttributeNames in interface AttributeList

getAttributeValues

public java.lang.Object[] getAttributeValues()

Specified by:

getAttributeValues in interface AttributeList

toStringFormat

public java.lang.String toStringFormat()

Deprecated. Use toStringFormat(boolean bSignature) instead

Converts the Key to a String representation. This is useful in that you can later materialize the Key object via it's string constructor. If bSignature is true, adds the Row handle as well as VO signature to the key string so that if a client connects to the same AM instance, the AM could find out the same VO and same Row based on these ids.

toByteArray

public byte[] toByteArray()

Deprecated. Use toByteArray(boolean bSignature) instead

Internal: em>Applications should not invoke this method.