oracle.ide.persistence

Interface Storage

public interface Storage

Provides access to a persistent storage area.

Since:

11.1.1.2

Method Summary

Methods

Modifier and Type	Method and Description
void	allowOpen() Allows the storage to be opened again.
void	close() Close the storage.
void	deleteNameSpace(java.lang.String name) Delete a namespace from this storage.
void	deleteNameSpace(java.lang.String name, java.util.Collection<java.lang.String> secondaryKeys) Delete a namespace from this storage, as well as any data for secondary keys associated with this namespace.
NameSpace	getNameSpace(java.lang.String name) Get a namespace from this storage.
NameSpace	getNameSpace(java.lang.String name, int type) Get a namespace from this storage.
NameSpace	getNameSpace(java.lang.String name, SecondaryKeyProvider provider) Get a namespace from this storage.
java.lang.String	getRelativePath(java.net.URL url) Get a path relative to this storage.
java.net.URL	getURL(java.lang.String relativePath) Get the URL for a relative path in the storage.
boolean	isOpen() Determine whether this storage is open.
boolean	isPinned() Determine whether this storage is pinned open.
void	lockClosed() Locks this storage closed.
void	open() Open the storage.
void	pin() Pins the storage open for faster access.
<T> T	runWhileClosed(java.util.concurrent.Callable<T> c) Run a task while the storage is closed.
void	runWhileClosed(java.lang.Runnable r) Run a task while the storage is closed.
<T> T	runWhileOpen(java.util.concurrent.Callable<T> c) Runs a task while the storage is open.
void	runWhileOpen(java.lang.Runnable r) Runs a task while the storage is open.
void	unpin() Unpins the storage.

Method Detail

getRelativePath

java.lang.String getRelativePath(@NotNull
                               java.net.URL url)

Get a path relative to this storage. This can be used to avoid storing abosolute paths in the storage, which helps make the storage files portable between machines. The storage must be open when this method is called.

Parameters:

url - the URL to make relative

Returns:

the relative path

Throws:

java.lang.IllegalStateException - if the storage is not open

See Also:

getURL(String)

getURL

java.net.URL getURL(@NotNull
                  java.lang.String relativePath)

Get the URL for a relative path in the storage. The storage must be open when this method is called.

Parameters:

relativePath - the relative path

Returns:

the URL

Throws:

java.lang.IllegalStateException - if the storage is not open

See Also:

getRelativePath(URL)

getNameSpace

NameSpace getNameSpace(@NotNull
                     java.lang.String name)

Get a namespace from this storage. The storage must be open when this method is called.

Parameters:

name - the name of the namespace

Returns:

the namespace

Throws:

java.lang.IllegalStateException - if the storage is not open

getNameSpace

NameSpace getNameSpace(@NotNull
                     java.lang.String name,
                     int type)

Get a namespace from this storage. The storage must be open when this method is called.

Parameters:

name - the name of the namespace

type - the type of namespace, either NameSpace.NSTYPE_NORMAL or NameSpace.NSTYPE_PACKED

Returns:

the namespace

Throws:

java.lang.IllegalStateException - if the storage is not open

getNameSpace

NameSpace getNameSpace(@NotNull
                     java.lang.String name,
                     @NotNull
                     SecondaryKeyProvider provider)

Get a namespace from this storage. The storage must be open when this method is called.

Parameters:

name - the name of the namespace

provider - the secondary key provider for the namespace

Returns:

the namespace

Throws:

java.lang.IllegalStateException - if the storage is not open

deleteNameSpace

void deleteNameSpace(@NotNull
                   java.lang.String name)

Delete a namespace from this storage. The storage must be open when this method is called.

Parameters:

name - the name of the namespace

Throws:

java.lang.IllegalStateException - if the storage is not open

deleteNameSpace

void deleteNameSpace(@NotNull
                   java.lang.String name,
                   @NotNull
                   java.util.Collection<java.lang.String> secondaryKeys)

Delete a namespace from this storage, as well as any data for secondary keys associated with this namespace. The storage must be open when this method is called.

Parameters:

name - the name of the namespace

secondaryKeys - secondary keys associated with this namespace

Throws:

java.lang.IllegalStateException - if the storage is not open

isOpen

boolean isOpen()

Determine whether this storage is open.

Returns:

true if the storage is open, false otherwise

open

void open()

Open the storage. Calls to this method must be paired with a call to close(). It is strongly recommended that runWhileOpen(Runnable) or runWhileOpen(Callable) be used instead of this method.

See Also:

close(), runWhileOpen(Runnable), runWhileOpen(Callable)

close

void close()

Close the storage. Calls to this method must be paired with a call to open(). It is strongly recommended that runWhileOpen(Runnable) or runWhileOpen(Callable) be used instead of this method.

See Also:

open(), runWhileOpen(Runnable), runWhileOpen(Callable)

runWhileOpen

void runWhileOpen(@NotNull
                java.lang.Runnable r)

Runs a task while the storage is open. This takes care of opening and closing the storage, even if the task throws an exception.

Parameters:

r - the task to run

runWhileOpen

<T> T runWhileOpen(@NotNull
                 java.util.concurrent.Callable<T> c)
               throws java.lang.Exception

Runs a task while the storage is open. This takes care of opening and closing the storage, even if the task throws an exception.

Type Parameters:

T - the type of value returned by the task

Parameters:

c - the task to run

Returns:

the return value of the task

Throws:

java.lang.Exception - if the task throws an exception

lockClosed

void lockClosed()

Locks this storage closed. This will block until the storage is not open. The storage will not be allowed to open again until allowOpen() is called. Great care must be taken when calling this method to avoid deadlock. This method should never be called while holding onto any other locks, such as Node locks. Doing so would cause deadlock with other threads that use the storage.

The calling thread must not call anything that requires the storage in between the calls to lockClosed and allowOpen. Doing so would cause deadlock.

The caller must ensure that for every call to this method, there is a corresponding call to allowOpen(). Failure to do so would result in the storage being locked permanently, blocking all future operations that need to use it. Typically, a caller should use a try/finally block to make sure that allowOpen() is always called.

This method is useful for situations where the storage file must be deleted or replaced while JDeveloper is running.

It is strongly recommended that runWhileClosed(Runnable) or runWhileClosed(Callable) be used instead of this method.

See Also:

allowOpen(), runWhileClosed(Runnable), runWhileClosed(Callable)

allowOpen

void allowOpen()

Allows the storage to be opened again. This must be paired with a call to lockClosed().

It is strongly recommended that runWhileClosed(Runnable) or runWhileClosed(Callable) be used instead of this method.

See Also:

lockClosed(), runWhileClosed(Runnable), runWhileClosed(Callable)

runWhileClosed

void runWhileClosed(@NotNull
                  java.lang.Runnable r)

Run a task while the storage is closed. This will block until the storage is no longer in use.

Parameters:

r - the task to run

runWhileClosed

<T> T runWhileClosed(@NotNull
                   java.util.concurrent.Callable<T> c)
                 throws java.lang.Exception

Run a task while the storage is closed. This will block until the storage is no longer in use.

Type Parameters:

T - the type of value returned by the task

Parameters:

c - the task to run

Returns:

the return value of the task

Throws:

java.lang.Exception - if the task throws an exception

pin

void pin()

Pins the storage open for faster access. Calls to this method must be paired with a corresponding call to unpin(). This is an optional operation. That is, the implementation may or may not support pinning, and the call may be ignored.

unpin

void unpin()

Unpins the storage.

isPinned

boolean isPinned()

Determine whether this storage is pinned open.

Returns:

true if the storage is pinned open, false otherwise