Sequence (EclipseLink 2.6.0, API Reference)

java.lang.Object
- org.eclipse.persistence.sequencing.Sequence

All Implemented Interfaces:

java.io.Serializable, java.lang.Cloneable

Direct Known Subclasses:

DefaultSequence, StandardSequence, UUIDSequence
```
public abstract class Sequence
extends java.lang.Object
implements java.io.Serializable, java.lang.Cloneable
```
Purpose: Abstract class to define sequencing.
Description A sequence defines how generated ids are obtained. The main sequence types are TableSequence and NativeSequence. Descriptors using sequencing will use the sequence object defined in their session's DatabaseLogin with the name matching their sequence name. If a specific sequence is not defined for the name the DatabaseLogin's default sequence will be used.

See Also:
TableSequence, NativeSequence, Serialized Form

Field Summary

Fields
Modifier and Type	Field and Description
`protected int`	`depth`
`protected int`	`initialValue`
`protected boolean`	`isCustomQualifier`
`protected java.lang.String`	`name`
`protected org.eclipse.persistence.internal.databaseaccess.Platform`	`platform`
`protected java.lang.String`	`qualifier`
`protected boolean`	`shouldAlwaysOverrideExistingValue`
`protected int`	`size`

Constructor Summary

Constructors
Constructor and Description
`Sequence()`
`Sequence(java.lang.String name)` Create a new sequence with the name.
`Sequence(java.lang.String name, int size)` Create a new sequence with the name and sequence pre-allocation size.
`Sequence(java.lang.String name, int size, int initialValue)`

Method Summary

Methods
Modifier and Type	Method and Description
`java.lang.Object`	`clone()`
`static boolean`	`equalNameAndSize(Sequence seq1, Sequence seq2)` INTERNAL: Used in equals.
`boolean`	`equals(java.lang.Object obj)`
`org.eclipse.persistence.internal.databaseaccess.Platform`	`getDatasourcePlatform()`
`java.lang.Object`	`getGeneratedValue(org.eclipse.persistence.internal.databaseaccess.Accessor accessor, org.eclipse.persistence.internal.sessions.AbstractSession writeSession)` INTERNAL: Return the newly-generated sequencing value.
`abstract java.lang.Object`	`getGeneratedValue(org.eclipse.persistence.internal.databaseaccess.Accessor accessor, org.eclipse.persistence.internal.sessions.AbstractSession writeSession, java.lang.String seqName)` INTERNAL: Return the newly-generated sequencing value.
`java.util.Vector`	`getGeneratedVector(org.eclipse.persistence.internal.databaseaccess.Accessor accessor, org.eclipse.persistence.internal.sessions.AbstractSession writeSession)` INTERNAL: Return a Vector of newly-generated sequencing values.
`abstract java.util.Vector`	`getGeneratedVector(org.eclipse.persistence.internal.databaseaccess.Accessor accessor, org.eclipse.persistence.internal.sessions.AbstractSession writeSession, java.lang.String seqName, int size)` INTERNAL: Return a Vector of newly-generated sequencing values.
`int`	`getInitialValue()`
`java.lang.String`	`getName()`
`int`	`getPreallocationSize()`
`java.lang.String`	`getQualified(java.lang.String str)` INTERNAL:
`java.lang.String`	`getQualifier()` INTERNAL:
`boolean`	`isConnected()` PUBLIC: Indicates that Sequence is connected.
`boolean`	`isCustomQualifier()` INTERNAL:
`boolean`	`isNative()`
`boolean`	`isTable()`
`boolean`	`isUnaryTable()`
`abstract void`	`onConnect()` INTERNAL: This method is called when Sequencing object is created.
`void`	`onConnect(org.eclipse.persistence.internal.databaseaccess.Platform platform)` INTERNAL: This method is called when Sequencing object is created.
`abstract void`	`onDisconnect()` INTERNAL: This method is called when Sequencing object is destroyed.
`void`	`onDisconnect(org.eclipse.persistence.internal.databaseaccess.Platform platform)` INTERNAL: This method is called when Sequencing object is destroyed.
`protected void`	`setDatasourcePlatform(org.eclipse.persistence.internal.databaseaccess.Platform platform)`
`void`	`setInitialValue(int initialValue)`
`void`	`setName(java.lang.String name)`
`void`	`setPreallocationSize(int size)`
`void`	`setQualifier(java.lang.String qualifier)` INTERNAL:
`void`	`setShouldAlwaysOverrideExistingValue(boolean shouldAlwaysOverrideExistingValue)` ADVANCED: Set that to true if the sequence should always override the existing pk value.
`abstract boolean`	`shouldAcquireValueAfterInsert()` INTERNAL: Indicates whether sequencing value should be acquired after INSERT.
`boolean`	`shouldAlwaysOverrideExistingValue()` INTERNAL: Indicates whether the existing pk value should always be overridden by the sequence.
`boolean`	`shouldAlwaysOverrideExistingValue(java.lang.String seqName)` INTERNAL: Indicates whether the existing pk value should always be overridden by the sequence.
`boolean`	`shouldUsePreallocation()` INTERNAL: Indicates whether several sequencing values should be acquired at a time and be kept by TopLink.
`abstract boolean`	`shouldUseTransaction()` INTERNAL: Indicates whether TopLink should internally call beginTransaction() before getGeneratedValue/Vector, and commitTransaction after.
`java.lang.String`	`toString()`
`protected void`	`verifyPlatform(org.eclipse.persistence.internal.databaseaccess.Platform otherPlatform)` INTERNAL: Make sure that the sequence is not used by more than one platform.

Methods inherited from class java.lang.Object
finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

- Field Detail
  - name
```
protected java.lang.String name
```
  - size
```
protected int size
```
  - platform
```
protected org.eclipse.persistence.internal.databaseaccess.Platform platform
```
  - initialValue
```
protected int initialValue
```
  - depth
```
protected int depth
```
  - qualifier
```
protected java.lang.String qualifier
```
  - isCustomQualifier
```
protected boolean isCustomQualifier
```
  - shouldAlwaysOverrideExistingValue
```
protected boolean shouldAlwaysOverrideExistingValue
```
- Constructor Detail
  - Sequence
```
public Sequence()
```
  - Sequence
```
public Sequence(java.lang.String name)
```
    Create a new sequence with the name.
  - Sequence
```
public Sequence(java.lang.String name,
        int size)
```
    Create a new sequence with the name and sequence pre-allocation size.
  - Sequence
```
public Sequence(java.lang.String name,
        int size,
        int initialValue)
```
- Method Detail
  - isNative
```
public boolean isNative()
```
  - isTable
```
public boolean isTable()
```
  - isUnaryTable
```
public boolean isUnaryTable()
```
  - getName
```
public java.lang.String getName()
```
  - setName
```
public void setName(java.lang.String name)
```
  - getPreallocationSize
```
public int getPreallocationSize()
```
  - setPreallocationSize
```
public void setPreallocationSize(int size)
```
  - getInitialValue
```
public int getInitialValue()
```
  - setInitialValue
```
public void setInitialValue(int initialValue)
```
  - clone
```
public java.lang.Object clone()
```
    Overrides:
    
    clone in class java.lang.Object
  - equals
```
public boolean equals(java.lang.Object obj)
```
    Overrides:
    
    equals in class java.lang.Object
  - equalNameAndSize
```
public static boolean equalNameAndSize(Sequence seq1,
                       Sequence seq2)
```
    INTERNAL: Used in equals.
  - setDatasourcePlatform
```
protected void setDatasourcePlatform(org.eclipse.persistence.internal.databaseaccess.Platform platform)
```
  - getDatasourcePlatform
```
public org.eclipse.persistence.internal.databaseaccess.Platform getDatasourcePlatform()
```
  - shouldAcquireValueAfterInsert
```
public abstract boolean shouldAcquireValueAfterInsert()
```
    INTERNAL: Indicates whether sequencing value should be acquired after INSERT. Note that preallocation could be used only in case sequencing values should be acquired before insert (this method returns false). In default implementation, it is true for table sequencing and native sequencing on Oracle platform, false for native sequencing on other platforms.
  - shouldUsePreallocation
```
public boolean shouldUsePreallocation()
```
    INTERNAL: Indicates whether several sequencing values should be acquired at a time and be kept by TopLink. This in only possible in case sequencing numbers should be acquired before insert (shouldAcquireValueAfterInsert()==false). In default implementation, it is true for table sequencing and native sequencing on Oracle platform, false for native sequencing on other platforms.
  - shouldUseTransaction
```
public abstract boolean shouldUseTransaction()
```
    INTERNAL: Indicates whether TopLink should internally call beginTransaction() before getGeneratedValue/Vector, and commitTransaction after. In default implementation, it is true for table sequencing and false for native sequencing.
  - getGeneratedValue
```
public abstract java.lang.Object getGeneratedValue(org.eclipse.persistence.internal.databaseaccess.Accessor accessor,
                                 org.eclipse.persistence.internal.sessions.AbstractSession writeSession,
                                 java.lang.String seqName)
```
    INTERNAL: Return the newly-generated sequencing value. Used only in case preallocation is not used (shouldUsePreallocation()==false). Accessor may be non-null only in case shouldUseSeparateConnection()==true. Even in this case accessor could be null - if SequencingControl().shouldUseSeparateConnection()==false; Therefore in case shouldUseSeparateConnection()==true, implementation should handle both cases: use a separate connection if provided (accessor != null), or get by without it (accessor == null).
    
    Parameters:
    accessor - Accessor is a separate sequencing accessor (may be null);
    writeSession - Session is a Session used for writing (either ClientSession or DatabaseSession);
    seqName - String is sequencing number field name
  - getGeneratedValue
```
public java.lang.Object getGeneratedValue(org.eclipse.persistence.internal.databaseaccess.Accessor accessor,
                                 org.eclipse.persistence.internal.sessions.AbstractSession writeSession)
```
    INTERNAL: Return the newly-generated sequencing value. Used only in case preallocation is not used (shouldUsePreallocation()==false). Accessor may be non-null only in case shouldUseSeparateConnection()==true. Even in this case accessor could be null - if SequencingControl().shouldUseSeparateConnection()==false; Therefore in case shouldUseSeparateConnection()==true, implementation should handle both cases: use a separate connection if provided (accessor != null), or get by without it (accessor == null).
    
    Parameters:
    accessor - Accessor is a separate sequencing accessor (may be null);
    writeSession - Session is a Session used for writing (either ClientSession or DatabaseSession);
  - getGeneratedVector
```
public abstract java.util.Vector getGeneratedVector(org.eclipse.persistence.internal.databaseaccess.Accessor accessor,
                                  org.eclipse.persistence.internal.sessions.AbstractSession writeSession,
                                  java.lang.String seqName,
                                  int size)
```
    INTERNAL: Return a Vector of newly-generated sequencing values. Used only in case preallocation is used (shouldUsePreallocation()==true). Accessor may be non-null only in case shouldUseSeparateConnection()==true. Even in this case accessor could be null - if SequencingControl().shouldUseSeparateConnection()==false; Therefore in case shouldUseSeparateConnection()==true, implementation should handle both cases: use a separate connection if provided (accessor != null), or get by without it (accessor == null).
    
    Parameters:
    accessor - Accessor is a separate sequencing accessor (may be null);
    writeSession - Session is a Session used for writing (either ClientSession or DatabaseSession);
    seqName - String is sequencing number field name
    size - int number of values to preallocate (output Vector size).
  - getGeneratedVector
```
public java.util.Vector getGeneratedVector(org.eclipse.persistence.internal.databaseaccess.Accessor accessor,
                                  org.eclipse.persistence.internal.sessions.AbstractSession writeSession)
```
    INTERNAL: Return a Vector of newly-generated sequencing values. Used only in case preallocation is used (shouldUsePreallocation()==true). Accessor may be non-null only in case shouldUseSeparateConnection()==true. Even in this case accessor could be null - if SequencingControl().shouldUseSeparateConnection()==false; Therefore in case shouldUseSeparateConnection()==true, implementation should handle both cases: use a separate connection if provided (accessor != null), or get by without it (accessor == null).
    
    Parameters:
    accessor - Accessor is a separate sequencing accessor (may be null);
    writeSession - Session is a Session used for writing (either ClientSession or DatabaseSession);
  - onConnect
```
public void onConnect(org.eclipse.persistence.internal.databaseaccess.Platform platform)
```
    INTERNAL: This method is called when Sequencing object is created. Don't override this method.
  - onConnect
```
public abstract void onConnect()
```
    INTERNAL: This method is called when Sequencing object is created. If it requires initialization, subclass should override this method.
  - onDisconnect
```
public void onDisconnect(org.eclipse.persistence.internal.databaseaccess.Platform platform)
```
    INTERNAL: This method is called when Sequencing object is destroyed. Don't override this method.
  - onDisconnect
```
public abstract void onDisconnect()
```
    INTERNAL: This method is called when Sequencing object is destroyed. If it requires deinitialization, subclass should override this method.
  - isConnected
```
public boolean isConnected()
```
    PUBLIC: Indicates that Sequence is connected.
  - verifyPlatform
```
protected void verifyPlatform(org.eclipse.persistence.internal.databaseaccess.Platform otherPlatform)
```
    INTERNAL: Make sure that the sequence is not used by more than one platform.
  - setQualifier
```
public void setQualifier(java.lang.String qualifier)
```
    INTERNAL:
  - isCustomQualifier
```
public boolean isCustomQualifier()
```
    INTERNAL:
  - getQualifier
```
public java.lang.String getQualifier()
```
    INTERNAL:
  - getQualified
```
public java.lang.String getQualified(java.lang.String str)
```
    INTERNAL:
  - setShouldAlwaysOverrideExistingValue
```
public void setShouldAlwaysOverrideExistingValue(boolean shouldAlwaysOverrideExistingValue)
```
    ADVANCED: Set that to true if the sequence should always override the existing pk value.
  - shouldAlwaysOverrideExistingValue
```
public boolean shouldAlwaysOverrideExistingValue()
```
    INTERNAL: Indicates whether the existing pk value should always be overridden by the sequence. As always the version of the method taking seqName is provided for the benefit of DefaultSequence.
  - shouldAlwaysOverrideExistingValue
```
public boolean shouldAlwaysOverrideExistingValue(java.lang.String seqName)
```
    INTERNAL: Indicates whether the existing pk value should always be overridden by the sequence.
  - toString
```
public java.lang.String toString()
```
    Overrides:
    
    toString in class java.lang.Object

Class Sequence

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

name

size

platform

initialValue

depth

qualifier

isCustomQualifier

shouldAlwaysOverrideExistingValue

Constructor Detail

Sequence

Sequence

Sequence

Sequence

Method Detail

isNative

isTable

isUnaryTable

getName

setName

getPreallocationSize

setPreallocationSize

getInitialValue

setInitialValue

clone

equals

equalNameAndSize

setDatasourcePlatform

getDatasourcePlatform

shouldAcquireValueAfterInsert

shouldUsePreallocation

shouldUseTransaction

getGeneratedValue

getGeneratedValue

getGeneratedVector

getGeneratedVector

onConnect

onConnect

onDisconnect

onDisconnect

isConnected

verifyPlatform

setQualifier

isCustomQualifier

getQualifier

getQualified

setShouldAlwaysOverrideExistingValue

shouldAlwaysOverrideExistingValue

shouldAlwaysOverrideExistingValue

toString