Package com.microej.kf.util.storage

Class SandboxedStorage

java.lang.Object

com.microej.kf.util.storage.SandboxedStorage

All Implemented Interfaces:

Storage

public class SandboxedStorage
extends Object
implements Storage

Extends the storage on file system to add sandboxing for the applications.

Constructor Summary

Constructors

Constructor	Description
SandboxedStorage()	Creates a sandboxed storage on file system.
SandboxedStorage(String root)	Creates a storage on file system specifying the root folder where the root folder will be created.

Method Summary

Modifier and Type	Method	Description
OutputStream	append(String s)	Appends some data to an entry referenced with an ID.
boolean	exists(String s)	Tests whether an entry exists for this ID.
String[]	getIds()	Returns all IDs of the stored entries.
String	getRootFolder(Module module)	Gets the root folder of the storage service for a given module.
long	getSize(String s)	Returns the size of the entry stored with an ID.
InputStream	load(String s)	Loads the data stored with a specific ID or null if there is none.
OutputStream	modify(String s, int i)	Modifies the entry that is referenced by an ID.
void	move(String s, String s1)	Changes the ID of an entry.
void	remove(String s)	Removes the entry stored with an ID.
OutputStream	store(String s)	Stores data that will be referenced with an ID.

Methods inherited from class java.lang.Object

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

Constructor Detail

SandboxedStorage

public SandboxedStorage()
                 throws IOException

Creates a sandboxed storage on file system.

The root folder is determined dynamically depending on the KF context. Each module has a different one.

Throws:

IOException - if the root cannot be created.

See Also:

Kernel.getContextOwner(), StorageFs()

SandboxedStorage

public SandboxedStorage(String root)
                 throws IOException

Creates a storage on file system specifying the root folder where the root folder will be created.

The root folder is determined dynamically depending on the KF context. Each module has a different one.

Parameters:

root - the root folder.

Throws:

IllegalArgumentException - if the root already exists and is not a directory.

IOException - if the root cannot be created.

Method Detail

getRootFolder

public String getRootFolder(Module module)

Gets the root folder of the storage service for a given module.

Parameters:

module - the module.

Returns:

the root folder.

store

public OutputStream store(String s)
                   throws IOException

Description copied from interface: Storage

Stores data that will be referenced with an ID.

If an entry is already stored with this ID, its existing data is fully removed and replaced by the given data. Otherwise, a new entry is created.

This operation may block the current thread depending on the implementation.

The returned output stream must be flushed or closed to ensure that the data is available. Example of usage:

 try(OutputStream outputStream = store(id)) {
        outputStream.write(…);
        outputStream.write(…);
 }
 

Specified by:

store in interface Storage

Parameters:

s - the ID of the stored entry.

Returns:

the output stream to write data.

Throws:

IOException - if an I/O error occurs.

modify

public OutputStream modify(String s,
                           int i)
                    throws IOException

Description copied from interface: Storage

Modifies the entry that is referenced by an ID.

If an entry is already stored with this ID, its existing data is not removed and only the targeted bytes will be overwritten. Otherwise, a new entry is created.

This operation may block the current thread depending on the implementation.

The returned output stream must be flushed or closed to ensure that the data is available.

Specified by:

modify in interface Storage

Parameters:

s - the ID of the stored entry.

i - the offset at which to write data.

Returns:

the output stream to write data.

Throws:

IOException - if an I/O error occurs.

append

public OutputStream append(String s)
                    throws IOException

Description copied from interface: Storage

Appends some data to an entry referenced with an ID.

If an entry is already stored with this ID, its existing data is not removed and the given data will be added to the existing entry. Otherwise, a new entry is created.

This operation may block the current thread depending on the implementation.

The returned output stream must be flushed or closed to ensure that the data is available. Example of usage:

 try(OutputStream outputStream = append(id)) {
        outputStream.write(…);
        outputStream.write(…);
 }
 

Specified by:

append in interface Storage

Parameters:

s - the ID of the stored entry.

Returns:

the output stream to write data.

Throws:

IOException - if an I/O error occurs.

load

public InputStream load(String s)
                 throws IOException

Description copied from interface: Storage

Loads the data stored with a specific ID or null if there is none.

The returned input stream must be closed by the caller.

This operation may block the current thread depending on the implementation.

Specified by:

load in interface Storage

Parameters:

s - the ID of the entry to be returned.

Returns:

the data of the entry stored with the given ID or null.

Throws:

IOException - if an I/O error occurs.

move

public void move(String s,
                 String s1)
          throws IOException

Description copied from interface: Storage

Changes the ID of an entry.

If an entry is already stored with the destination ID, it is overwritten.

This operation may block the current thread depending on the implementation.

Specified by:

move in interface Storage

Parameters:

s - the old ID of the entry.

s1 - the new ID of the entry.

Throws:

IOException - if an I/O error occurs.

remove

public void remove(String s)
            throws IOException

Description copied from interface: Storage

Removes the entry stored with an ID.

This operation may block the current thread depending on the implementation.

Specified by:

remove in interface Storage

Parameters:

s - the ID of the entry to remove.

Throws:

IOException - if an I/O error occurs.

getSize

public long getSize(String s)
             throws IOException

Description copied from interface: Storage

Returns the size of the entry stored with an ID.

Specified by:

getSize in interface Storage

Parameters:

s - the ID of the entry.

Returns:

the size of the entry.

Throws:

IOException - if an I/O error occurs.

exists

public boolean exists(String s)
               throws IOException

Description copied from interface: Storage

Tests whether an entry exists for this ID.

Specified by:

exists in interface Storage

Parameters:

s - the ID to check.

Returns:

true if the given ID exists, false otherwise

Throws:

IOException - if an I/O error occurs.

getIds

public String[] getIds()
                throws IOException

Description copied from interface: Storage

Returns all IDs of the stored entries.

Specified by:

getIds in interface Storage

Returns:

an array of all IDs.

Throws:

IOException - if an I/O error occurs.