Package py4j

Class Gateway

  • public class Gateway
extends java.lang.Object

    A Gateway manages various states: entryPoint, references to objects returned to a Python program, etc.

    This class is not intended to be directly accessed by users.

    • Constructor Summary

      Constructors 
      Constructor Description
      Gateway​(java.lang.Object entryPoint)  
      Gateway​(java.lang.Object entryPoint, Py4JPythonClient cbClient)  

    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      void closeConnection()
      Called when a connection is closed.
      java.lang.Object createProxy​(java.lang.ClassLoader classLoader, java.lang.Class[] interfacesToImplement, java.lang.String objectId)
      Creates a proxy implementing the provided interfaces with the provided class loader.
      protected PythonProxyHandler createPythonProxyHandler​(java.lang.String id)  
      void deleteObject​(java.lang.String objectId)  
      protected java.util.concurrent.atomic.AtomicInteger getArgCounter()  
      java.util.Map<java.lang.String,​java.lang.Object> getBindings()  
      Py4JPythonClient getCallbackClient()  
      JVMView getDefaultJVMView()  
      java.lang.Object getEntryPoint()  
      protected java.lang.String getNextObjectId()  
      protected java.util.concurrent.atomic.AtomicInteger getObjCounter()  
      java.lang.Object getObject​(java.lang.String objectId)  
      protected java.lang.Object getObjectFromId​(java.lang.String targetObjectId)  
      ReflectionEngine getReflectionEngine()  
      ReturnObject getReturnObject​(java.lang.Object object)  
      ReturnObject invoke​(java.lang.String methodName, java.lang.String targetObjectId, java.util.List<java.lang.Object> args)
      Invokes a method.
      ReturnObject invoke​(java.lang.String fqn, java.util.List<java.lang.Object> args)
      Invokes a constructor and returned the constructed object.
      protected boolean isArray​(java.lang.Object object)  
      protected boolean isDecimalObject​(java.lang.Object object)  
      protected boolean isList​(java.lang.Object object)  
      protected boolean isMap​(java.lang.Object object)  
      protected boolean isPrimitiveObject​(java.lang.Object object)  
      protected boolean isSet​(java.lang.Object object)  
      boolean isStarted()  
      java.lang.String putNewObject​(java.lang.Object object)
      Adds a new object to the gateway bindings and return the generated ID.
      java.lang.Object putObject​(java.lang.String id, java.lang.Object object)  
      void resetCallbackClient​(java.net.InetAddress pythonAddress, int pythonPort)
      Replace the callback client with the new one which connects to the given address and port.
      void setStarted​(boolean isStarted)  
      void shutdown()
      Releases all objects that were referenced by this Gateway and shuts down the CallbackClient.
      void shutdown​(boolean shutdownCallbackClient)
      Releases all objects that were referenced by this Gateway and optionally shut down the callback client.
      void startup()  

      • Methods inherited from class java.lang.Object

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

    • Constructor Detail

      • Gateway

        public Gateway​(java.lang.Object entryPoint)

      • Gateway

        public Gateway​(java.lang.Object entryPoint,
               Py4JPythonClient cbClient)

    • Method Detail

      • resetCallbackClient

        public void resetCallbackClient​(java.net.InetAddress pythonAddress,
                                int pythonPort)

        Replace the callback client with the new one which connects to the given address and port. This method is useful if for some reason your CallbackServer changes its address or you come to know of the address after Gateway has already instantiated.

        This method is not thread-safe! Make sure that only one thread calls this method.

        Parameters:
        pythonAddress - The address used by a PythonProxyHandler to connect to a Python gateway.
        pythonPort - The port used by a PythonProxyHandler to connect to a Python gateway. Essentially the port used for Python callbacks.

      • closeConnection

        public void closeConnection()

        Called when a connection is closed.

      • deleteObject

        public void deleteObject​(java.lang.String objectId)

      • getArgCounter

        protected java.util.concurrent.atomic.AtomicInteger getArgCounter()

      • getBindings

        public java.util.Map<java.lang.String,​java.lang.Object> getBindings()
        Returns:
        The bindings of the Gateway. Should never be called by other classes except subclasses and testing classes.

      • getDefaultJVMView

        public JVMView getDefaultJVMView()

      • getEntryPoint

        public java.lang.Object getEntryPoint()

      • getNextObjectId

        protected java.lang.String getNextObjectId()

      • getObjCounter

        protected java.util.concurrent.atomic.AtomicInteger getObjCounter()

      • getObject

        public java.lang.Object getObject​(java.lang.String objectId)
        Parameters:
        objectId -
        Returns:
        The object associated with the id or null if the object id is unknown.

      • getObjectFromId

        protected java.lang.Object getObjectFromId​(java.lang.String targetObjectId)

      • getReturnObject

        public ReturnObject getReturnObject​(java.lang.Object object)

      • invoke

        public ReturnObject invoke​(java.lang.String fqn,
                           java.util.List<java.lang.Object> args)

        Invokes a constructor and returned the constructed object.

        Parameters:
        fqn - The fully qualified name of the class.
        args -
        Returns:

      • invoke

        public ReturnObject invoke​(java.lang.String methodName,
                           java.lang.String targetObjectId,
                           java.util.List<java.lang.Object> args)

        Invokes a method.

        Parameters:
        methodName -
        targetObjectId -
        args -
        Returns:

      • isArray

        protected boolean isArray​(java.lang.Object object)

      • isDecimalObject

        protected boolean isDecimalObject​(java.lang.Object object)

      • isList

        protected boolean isList​(java.lang.Object object)

      • isMap

        protected boolean isMap​(java.lang.Object object)

      • isPrimitiveObject

        protected boolean isPrimitiveObject​(java.lang.Object object)

      • isSet

        protected boolean isSet​(java.lang.Object object)

      • isStarted

        public boolean isStarted()

      • putNewObject

        public java.lang.String putNewObject​(java.lang.Object object)

        Adds a new object to the gateway bindings and return the generated ID. Should NEVER be called by other classes except subclasses and testing classes.

        Parameters:
        object -
        Returns:

      • putObject

        public java.lang.Object putObject​(java.lang.String id,
                                  java.lang.Object object)

      • setStarted

        public void setStarted​(boolean isStarted)

      • createProxy

        public java.lang.Object createProxy​(java.lang.ClassLoader classLoader,
                                    java.lang.Class[] interfacesToImplement,
                                    java.lang.String objectId)

        Creates a proxy implementing the provided interfaces with the provided class loader.

        This method is part of the Gateway instance to allow overriding or customizing per Gateway instance.

        Parameters:
        classLoader -
        interfacesToImplement -
        objectId -
        Returns:

      • createPythonProxyHandler

        protected PythonProxyHandler createPythonProxyHandler​(java.lang.String id)

      • shutdown

        public void shutdown()

        Releases all objects that were referenced by this Gateway and shuts down the CallbackClient.

      • shutdown

        public void shutdown​(boolean shutdownCallbackClient)

        Releases all objects that were referenced by this Gateway and optionally shut down the callback client.

        Parameters:
        shutdownCallbackClient - Shuts down the CallbackClient instance if true.

      • startup

        public void startup()