IT. Expert System.

All Implemented Interfaces:

IBinder

Direct Known Subclasses:

ActivityManagerNative, ApplicationThreadNative, BulkCursorNative, ContentProviderNative, IMountService.Stub, IMountServiceListener.Stub, IMountShutdownObserver.Stub, IObbActionListener.Stub, ServiceManagerNative

public class Binder
extends Object
implements IBinder

See Also:

IBinder

• Nested Class Summary

  • Nested classes/interfaces inherited from interface android.os.IBinder

    IBinder.DeathRecipient

• Field Summary

  • Fields inherited from interface android.os.IBinder

    DUMP_TRANSACTION, FIRST_CALL_TRANSACTION, FLAG_ONEWAY, INTERFACE_TRANSACTION, LAST_CALL_TRANSACTION, LIKE_TRANSACTION, PING_TRANSACTION, SYSPROPS_TRANSACTION, TWEET_TRANSACTION

• Constructor Summary

  Constructors

  Constructor and Description
  Binder() Default constructor initializes the object.

• Method Summary

  Methods

  Modifier and Type	Method and Description
  void	attachInterface(IInterface owner, String descriptor) Convenience method for associating a specific interface with the Binder.
  static long	clearCallingIdentity() Reset the identity of the incoming IPC on the current thread.
  protected void	dump(FileDescriptor fd, PrintWriter fout, String[] args) Print the object's state into the given stream.
  void	dump(FileDescriptor fd, String[] args) Implemented to call the more convenient version dump(FileDescriptor, PrintWriter, String[]).
  void	dumpAsync(FileDescriptor fd, String[] args) Like dump(FileDescriptor, String[]), but ensures the target executes asynchronously.
  protected void	finalize() Invoked when the garbage collector has detected that this instance is no longer reachable.
  static void	flushPendingCommands() Flush any Binder commands pending in the current thread to the kernel driver.
  static int	getCallingPid() Return the ID of the process that sent you the current transaction that is being processed.
  static int	getCallingUid() Return the Linux uid assigned to the process that sent you the current transaction that is being processed.
  static UserHandle	getCallingUserHandle() Return the UserHandle assigned to the process that sent you the current transaction that is being processed.
  String	getInterfaceDescriptor() Default implementation returns an empty interface name.
  static int	getThreadStrictModePolicy() Gets the current native thread-local StrictMode policy mask.
  boolean	isBinderAlive() Check to see if the process that the binder is in is still alive.
  static void	joinThreadPool() Add the calling thread to the IPC thread pool.
  void	linkToDeath(IBinder.DeathRecipient recipient, int flags) Local implementation is a no-op.
  protected boolean	onTransact(int code, Parcel data, Parcel reply, int flags) Default implementation is a stub that returns false.
  boolean	pingBinder() Default implementation always returns true -- if you got here, the object is alive.
  IInterface	queryLocalInterface(String descriptor) Use information supplied to attachInterface() to return the associated IInterface if it matches the requested descriptor.
  static void	restoreCallingIdentity(long token) Restore the identity of the incoming IPC on the current thread back to a previously identity that was returned by clearCallingIdentity().
  static void	setThreadStrictModePolicy(int policyMask) Sets the native thread-local StrictMode policy mask.
  boolean	transact(int code, Parcel data, Parcel reply, int flags) Default implementation rewinds the parcels and calls onTransact.
  boolean	unlinkToDeath(IBinder.DeathRecipient recipient, int flags) Local implementation is a no-op.

  • Methods inherited from class java.lang.Object

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

• Constructor Detail

  • Binder

    public Binder()

    Default constructor initializes the object.

• Method Detail

  • getCallingPid

    public static final int getCallingPid()

    Return the ID of the process that sent you the current transaction that is being processed. This pid can be used with higher-level system services to determine its identity and check permissions. If the current thread is not currently executing an incoming transaction, then its own pid is returned.

  • getCallingUid

    public static final int getCallingUid()

    Return the Linux uid assigned to the process that sent you the current transaction that is being processed. This uid can be used with higher-level system services to determine its identity and check permissions. If the current thread is not currently executing an incoming transaction, then its own uid is returned.

  • getCallingUserHandle

    public static final UserHandle getCallingUserHandle()

    Return the UserHandle assigned to the process that sent you the current transaction that is being processed. This is the user of the caller. It is distinct from getCallingUid() in that a particular user will have multiple distinct apps running under it each with their own uid. If the current thread is not currently executing an incoming transaction, then its own UserHandle is returned.

  • clearCallingIdentity

    public static final long clearCallingIdentity()

    Reset the identity of the incoming IPC on the current thread. This can be useful if, while handling an incoming call, you will be calling on interfaces of other objects that may be local to your process and need to do permission checks on the calls coming into them (so they will check the permission of your own local process, and not whatever process originally called you).

    Returns:

    Returns an opaque token that can be used to restore the original calling identity by passing it to restoreCallingIdentity(long).

    See Also:

    getCallingPid(), getCallingUid(), restoreCallingIdentity(long)

  • restoreCallingIdentity

    public static final void restoreCallingIdentity(long token)

    Restore the identity of the incoming IPC on the current thread back to a previously identity that was returned by clearCallingIdentity().

    Parameters:

    token - The opaque token that was previously returned by clearCallingIdentity().

    See Also:

    clearCallingIdentity()

  • setThreadStrictModePolicy

    public static final void setThreadStrictModePolicy(int policyMask)

    Sets the native thread-local StrictMode policy mask.

    The StrictMode settings are kept in two places: a Java-level threadlocal for libcore/Dalvik, and a native threadlocal (set here) for propagation via Binder calls. This is a little unfortunate, but necessary to break otherwise more unfortunate dependencies either of Dalvik on Android, or Android native-only code on Dalvik.

    See Also:

    StrictMode

  • getThreadStrictModePolicy

    public static final int getThreadStrictModePolicy()

    Gets the current native thread-local StrictMode policy mask.

    See Also:

    setThreadStrictModePolicy(int)

  • flushPendingCommands

    public static final void flushPendingCommands()

    Flush any Binder commands pending in the current thread to the kernel driver. This can be useful to call before performing an operation that may block for a long time, to ensure that any pending object references have been released in order to prevent the process from holding on to objects longer than it needs to.

  • joinThreadPool

    public static final void joinThreadPool()

    Add the calling thread to the IPC thread pool. This function does not return until the current process is exiting.

  • attachInterface

    public void attachInterface(IInterface owner,
                       String descriptor)

    Convenience method for associating a specific interface with the Binder. After calling, queryLocalInterface() will be implemented for you to return the given owner IInterface when the corresponding descriptor is requested.

  • getInterfaceDescriptor

    public String getInterfaceDescriptor()

    Default implementation returns an empty interface name.

    Specified by:

    getInterfaceDescriptor in interface IBinder

  • pingBinder

    public boolean pingBinder()

    Default implementation always returns true -- if you got here, the object is alive.

    Specified by:

    pingBinder in interface IBinder

    Returns:

    Returns false if the hosting process is gone, otherwise the result (always by default true) returned by the pingBinder() implementation on the other side.

  • isBinderAlive

    public boolean isBinderAlive()

    Check to see if the process that the binder is in is still alive. Note that if you're calling on a local binder, this always returns true because your process is alive if you're calling it.

    Specified by:

    isBinderAlive in interface IBinder

    Returns:

    false if the process is not alive. Note that if it returns true, the process may have died while the call is returning.

  • queryLocalInterface

    public IInterface queryLocalInterface(String descriptor)

    Use information supplied to attachInterface() to return the associated IInterface if it matches the requested descriptor.

    Specified by:

    queryLocalInterface in interface IBinder

  • onTransact

    protected boolean onTransact(int code,
                     Parcel data,
                     Parcel reply,
                     int flags)
                          throws RemoteException

    Default implementation is a stub that returns false. You will want to override this to do the appropriate unmarshalling of transactions.

    If you want to call this, call transact().

    Throws:

    RemoteException

  • dump

    public void dump(FileDescriptor fd,
            String[] args)

    Implemented to call the more convenient version dump(FileDescriptor, PrintWriter, String[]).

    Specified by:

    dump in interface IBinder

    Parameters:

    fd - The raw file descriptor that the dump is being sent to.

    args - additional arguments to the dump request.

  • dumpAsync

    public void dumpAsync(FileDescriptor fd,
                 String[] args)

    Like dump(FileDescriptor, String[]), but ensures the target executes asynchronously.

    Specified by:

    dumpAsync in interface IBinder

    Parameters:

    fd - The raw file descriptor that the dump is being sent to.

    args - additional arguments to the dump request.

  • dump

    protected void dump(FileDescriptor fd,
            PrintWriter fout,
            String[] args)

    Print the object's state into the given stream.

    Parameters:

    fd - The raw file descriptor that the dump is being sent to.

    fout - The file to which you should dump your state. This will be closed for you after you return.

    args - additional arguments to the dump request.

  • transact

    public final boolean transact(int code,
                   Parcel data,
                   Parcel reply,
                   int flags)
                           throws RemoteException

    Default implementation rewinds the parcels and calls onTransact. On the remote side, transact calls into the binder to do the IPC.

    Specified by:

    transact in interface IBinder

    Parameters:

    code - The action to perform. This should be a number between IBinder.FIRST_CALL_TRANSACTION and IBinder.LAST_CALL_TRANSACTION.

    data - Marshalled data to send to the target. Must not be null. If you are not sending any data, you must create an empty Parcel that is given here.

    reply - Marshalled data to be received from the target. May be null if you are not interested in the return value.

    flags - Additional operation flags. Either 0 for a normal RPC, or IBinder.FLAG_ONEWAY for a one-way RPC.

    Throws:

    RemoteException

  • linkToDeath

    public void linkToDeath(IBinder.DeathRecipient recipient,
                   int flags)

    Local implementation is a no-op.

    Specified by:

    linkToDeath in interface IBinder

    See Also:

    IBinder.unlinkToDeath(android.os.IBinder.DeathRecipient, int)

  • unlinkToDeath

    public boolean unlinkToDeath(IBinder.DeathRecipient recipient,
                        int flags)

    Local implementation is a no-op.

    Specified by:

    unlinkToDeath in interface IBinder

    Returns:

    Returns true if the recipient is successfully unlinked, assuring you that its DeathRecipient.binderDied() method will not be called. Returns false if the target IBinder has already died, meaning the method has been (or soon will be) called.

  • finalize

    protected void finalize()
                     throws Throwable

    Description copied from class: Object
    Invoked when the garbage collector has detected that this instance is no longer reachable. The default implementation does nothing, but this method can be overridden to free resources.

    Note that objects that override finalize are significantly more expensive than objects that don't. Finalizers may be run a long time after the object is no longer reachable, depending on memory pressure, so it's a bad idea to rely on them for cleanup. Note also that finalizers are run on a single VM-wide finalizer thread, so doing blocking work in a finalizer is a bad idea. A finalizer is usually only necessary for a class that has a native peer and needs to call a native method to destroy that peer. Even then, it's better to provide an explicit close method (and implement Closeable), and insist that callers manually dispose of instances. This works well for something like files, but less well for something like a BigInteger where typical calling code would have to deal with lots of temporaries. Unfortunately, code that creates lots of temporaries is the worst kind of code from the point of view of the single finalizer thread.

    If you must use finalizers, consider at least providing your own ReferenceQueue and having your own thread process that queue.

    Unlike constructors, finalizers are not automatically chained. You are responsible for calling super.finalize() yourself.

    Uncaught exceptions thrown by finalizers are ignored and do not terminate the finalizer thread. See Effective Java Item 7, "Avoid finalizers" for more.

    Overrides:

    finalize in class Object

    Throws:

    Throwable