oracle.javatools.db

Class DBObjectLister

java.lang.Object

oracle.javatools.db.DBObjectLister

public abstract class DBObjectLister
extends java.lang.Object

Plugin to DBObjectProvider to allow objects to be listed. A lister can be responsible for listing multiple object types.

Extensions to the API can register DBObjectListers using the DBObjectRegistry. If the same DBObjectLister is registered for multiple object types, and a list query is made against the provider for more than one of those types, the DBObjectLister should only be called once to list all the registered types.

Since:

11.1.1.4.0

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	DBObjectLister.ObjectInfo Encapsulates the information required about a listed object.

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	DBObjectLister(DBObjectProvider pro) Creates a new DBObjectLister.

Method Summary

Methods

Modifier and Type	Method and Description
boolean	equals(java.lang.Object obj) If two DBObjectListener implementations are equal, then a list query for multiple types will be made only once.
java.lang.Long	getExternalTimestamp(SystemObject obj) Gets the timestamp for the given object from the underlying metadata.
protected DBObjectProvider	getProvider() Gets the provider we are listing objects for.
int	hashCode() The default hashCode implementation for DBObjectLister matches the equals implementation and uses the object's class as the identifier.
abstract java.util.Collection<DBObjectLister.ObjectInfo>	listObjects(DBObjectCriteria criteria) List the objects that the given criteria has restricted the list to.
boolean	supportsTimestamps(java.lang.String objectType) Tests whether this lister supports timestamps for the given object type.

Methods inherited from class java.lang.Object

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

Constructor Detail

DBObjectLister

protected DBObjectLister(DBObjectProvider pro)

Creates a new DBObjectLister. All implementations must have a constructor that takes a DBObjectProvider and passes it to this constructor.

Parameters:

pro - the provider we are listing objects for.

Method Detail

getProvider

protected DBObjectProvider getProvider()

Gets the provider we are listing objects for.

listObjects

public abstract java.util.Collection<DBObjectLister.ObjectInfo> listObjects(DBObjectCriteria criteria)
                                                                     throws DBException

List the objects that the given criteria has restricted the list to.

Parameters:

criteria - use to determine type/name/schema criteria for the listing

Throws:

DBException

supportsTimestamps

public boolean supportsTimestamps(java.lang.String objectType)

Tests whether this lister supports timestamps for the given object type. If this is overridden to return true, getExternalTimestamp(SystemObject) must also be overridden to return the timestamp.

In addition the listObjects(oracle.javatools.db.DBObjectCriteria) implementation should include timestamps for the objects listed.

Parameters:

objectType - the object type

Returns:

true if this lister can query timestamps for the given object type.

getExternalTimestamp

public java.lang.Long getExternalTimestamp(SystemObject obj)
                                    throws DBException

Gets the timestamp for the given object from the underlying metadata. This will only be called if supportsTimestamps(String) returns true for the object's type.

Returns:

a timestamp for the object, or null if it doesn't have one.

Throws:

DBException

equals

public boolean equals(java.lang.Object obj)

If two DBObjectListener implementations are equal, then a list query for multiple types will be made only once. The default implementation compares the underlying provider, and the class of the lister (because the DBObjectRegistry takes the class for registration and then instantiates it with a provider).

Overrides:

equals in class java.lang.Object

Parameters:

obj - the other object to compare

Returns:

true if other is a lister and its list capabilities are identical to this object.

hashCode

public int hashCode()

The default hashCode implementation for DBObjectLister matches the equals implementation and uses the object's class as the identifier.

Overrides:

hashCode in class java.lang.Object

Returns:

a hash code for this object

See Also:

equals(Object)