net.cnri.apps.doserver

Class ConcreteStorageProxy

java.lang.Object

net.cnri.apps.doserver.ConcreteStorageProxy

All Implemented Interfaces:

StorageProxy

public final class ConcreteStorageProxy
extends java.lang.Object
implements StorageProxy

ConcreteStorageProxy objects provide an interface to the hash-based storage layer of the DO server.

Constructor Summary

Constructors

Constructor and Description
ConcreteStorageProxy(Storage storage, java.lang.String repositoryID, java.lang.String objectID, HeaderSet txnMetadata) Construct a storage accessor/proxy object that uses the given storage mechanism and restricts access to the given objectID based on the permissions granted to the given callerIDs.

Method Summary

Methods

Modifier and Type	Method and Description
void	appendDataElement(java.lang.String elementID, java.io.InputStream input) Appends the bytes from the given input stream to the given data element for the object.
java.lang.String	createObject(java.lang.String newObjectID) Creates a new digital object with the given ID, if one does not already exist.
java.lang.String	createObject(java.lang.String newObjectID, java.lang.String newObjectName) Creates a new digital object with the given ID, if one does not already exist.
void	deleteAttributes(java.lang.String[] attributeKeys) Remove the attributes with the given keys from the object.
boolean	deleteDataElement(java.lang.String elementID) Deletes the specified data element from the current object.
void	deleteElementAttributes(java.lang.String elementID, java.lang.String[] attributeKeys) Remove the attributes with the given keys from the element.
void	deleteObject() Deletes the digital object along with all data elements or files that are associated with it.
void	deserializeObject(java.lang.String format, java.io.InputStream in) Reset the object's state and re-initialize it with the data in the given InputStream in the given format.
boolean	doesDataElementExist(java.lang.String elementID) Returns true if the given data element exists
boolean	doesObjectExist() Returns true if the given digital object exists.
HeaderSet	getAttributes(HeaderSet container) Get all of the key-value attributes that are associated with the object.
java.io.InputStream	getDataElement(java.lang.String elementID) Returns the identified data element for this object.
HeaderSet	getElementAttributes(java.lang.String elementID, HeaderSet container) Get all of the key-value attributes that are associated with the given element in the object.
java.io.File	getFileForDataElement(java.lang.String elementID) Returns the File in which the given data element is stored, if any.
StorageProxy	getObjectAccessor(java.lang.String objectID) Returns a StorageProxy for a different object in this Repository.
java.lang.String	getObjectID() Get the object identifier of the given object.
java.lang.String	getRepoID() Get the repository identifier of the repository for the given object.
java.util.Enumeration	listDataElements() Returns a list of the data elements associated with the current object.
java.util.Enumeration	listObjects() Returns an Enumeration of all of the objects in the repository.
void	serializeObject(java.lang.String format, java.io.OutputStream out) Serialize the entire object using the given format to the given stream
void	setAttributes(HeaderSet attributes) Set the given key-value attributes in the object, replacing any existing attributes that have the same keys.
void	setElementAttributes(java.lang.String elementID, HeaderSet attributes) Set the given key-value attributes for the given element in the object, replacing any existing attributes that have the same keys.
void	storeDataElement(java.lang.String elementID, java.io.InputStream input) Stores the bytes from the given input stream into the given data element for the object.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

ConcreteStorageProxy

public ConcreteStorageProxy(Storage storage,
                    java.lang.String repositoryID,
                    java.lang.String objectID,
                    HeaderSet txnMetadata)

Construct a storage accessor/proxy object that uses the given storage mechanism and restricts access to the given objectID based on the permissions granted to the given callerIDs.

Method Detail

getObjectID

public java.lang.String getObjectID()

Get the object identifier of the given object.

Specified by:

getObjectID in interface StorageProxy

getRepoID

public java.lang.String getRepoID()

Get the repository identifier of the repository for the given object.

Specified by:

getRepoID in interface StorageProxy

getObjectAccessor

public StorageProxy getObjectAccessor(java.lang.String objectID)

Returns a StorageProxy for a different object in this Repository. The new StorageProxy will have the same access restrictions and parameters as this StorageProxy for the new object.

Specified by:

getObjectAccessor in interface StorageProxy

doesObjectExist

public boolean doesObjectExist()
                        throws DOException

Returns true if the given digital object exists.

Specified by:

doesObjectExist in interface StorageProxy

Throws:

DOException

doesDataElementExist

public boolean doesDataElementExist(java.lang.String elementID)
                             throws DOException

Returns true if the given data element exists

Specified by:

doesDataElementExist in interface StorageProxy

Throws:

DOException

getFileForDataElement

public java.io.File getFileForDataElement(java.lang.String elementID)
                                   throws DOException

Returns the File in which the given data element is stored, if any. This can return null on servers where data elements are not stored in files. This is used where operators need to do more with a data element than simple read and write operations. Examples inlude indexes, databases, etc.

Specified by:

getFileForDataElement in interface StorageProxy

Throws:

DOException

createObject

public java.lang.String createObject(java.lang.String newObjectID)
                              throws DOException

Creates a new digital object with the given ID, if one does not already exist. The caller must have permission to create a digital object, and the current object must represent the current data storage. This returns the ID of the newly created object.

Specified by:

createObject in interface StorageProxy

Throws:

DOException

deleteObject

public void deleteObject()
                  throws DOException

Deletes the digital object along with all data elements or files that are associated with it.

Specified by:

deleteObject in interface StorageProxy

Throws:

DOException

createObject

public java.lang.String createObject(java.lang.String newObjectID,
                            java.lang.String newObjectName)
                              throws DOException

Creates a new digital object with the given ID, if one does not already exist. The caller must have permission to create a digital object, and the current object must represent the current data storage. This returns the ID of the newly created object.

Specified by:

createObject in interface StorageProxy

Throws:

DOException

listObjects

public java.util.Enumeration listObjects()
                                  throws DOException

Returns an Enumeration of all of the objects in the repository.

Specified by:

listObjects in interface StorageProxy

Throws:

DOException

listDataElements

public java.util.Enumeration listDataElements()
                                       throws DOException

Returns a list of the data elements associated with the current object.

Specified by:

listDataElements in interface StorageProxy

Throws:

DOException

getDataElement

public java.io.InputStream getDataElement(java.lang.String elementID)
                                   throws DOException

Returns the identified data element for this object. If the caller does not have permission to read this stream, a DOException is thrown with code PERMISSION_DENIED_ERROR.

Specified by:

getDataElement in interface StorageProxy

Throws:

DOException

storeDataElement

public void storeDataElement(java.lang.String elementID,
                    java.io.InputStream input)
                      throws java.lang.Exception

Stores the bytes from the given input stream into the given data element for the object.

Specified by:

storeDataElement in interface StorageProxy

Throws:

java.lang.Exception

appendDataElement

public void appendDataElement(java.lang.String elementID,
                     java.io.InputStream input)
                       throws java.lang.Exception

Appends the bytes from the given input stream to the given data element for the object.

Specified by:

appendDataElement in interface StorageProxy

Throws:

java.lang.Exception

deleteDataElement

public boolean deleteDataElement(java.lang.String elementID)
                          throws DOException

Deletes the specified data element from the current object. Returns true if the specified data element ever existed in the first place.

Specified by:

deleteDataElement in interface StorageProxy

Throws:

DOException

getAttributes

public HeaderSet getAttributes(HeaderSet container)
                        throws DOException

Get all of the key-value attributes that are associated with the object. If the given container is non-null then the attributes are put into it in order to avoid instantiating a new HeaderSet.

Specified by:

getAttributes in interface StorageProxy

Returns:

a HeaderSet containing all of the attributes that are associated with the object

Throws:

DOException

getElementAttributes

public HeaderSet getElementAttributes(java.lang.String elementID,
                             HeaderSet container)
                               throws DOException

Get all of the key-value attributes that are associated with the given element in the object. If the given container is non-null then the attributes are put into it in order to avoid instantiating a new HeaderSet.

Specified by:

getElementAttributes in interface StorageProxy

Returns:

a HeaderSet containing all of the attributes that are associated with the element

Throws:

DOException

setAttributes

public void setAttributes(HeaderSet attributes)
                   throws DOException

Set the given key-value attributes in the object, replacing any existing attributes that have the same keys. This will not remove any attributes from the object.

Specified by:

setAttributes in interface StorageProxy

Throws:

DOException

setElementAttributes

public void setElementAttributes(java.lang.String elementID,
                        HeaderSet attributes)
                          throws DOException

Set the given key-value attributes for the given element in the object, replacing any existing attributes that have the same keys. This will not remove any attributes from the element

Specified by:

setElementAttributes in interface StorageProxy

Throws:

DOException

deleteAttributes

public void deleteAttributes(java.lang.String[] attributeKeys)
                      throws DOException

Remove the attributes with the given keys from the object.

Specified by:

deleteAttributes in interface StorageProxy

Throws:

DOException

deleteElementAttributes

public void deleteElementAttributes(java.lang.String elementID,
                           java.lang.String[] attributeKeys)
                             throws DOException

Remove the attributes with the given keys from the element.

Specified by:

deleteElementAttributes in interface StorageProxy

Throws:

DOException

serializeObject

public void serializeObject(java.lang.String format,
                   java.io.OutputStream out)
                     throws DOException

Serialize the entire object using the given format to the given stream

Specified by:

serializeObject in interface StorageProxy

Throws:

DOException

deserializeObject

public void deserializeObject(java.lang.String format,
                     java.io.InputStream in)
                       throws DOException

Reset the object's state and re-initialize it with the data in the given InputStream in the given format.

Specified by:

deserializeObject in interface StorageProxy

Throws:

DOException