Package org.apache.ignite.marshaller

## Interface Marshaller

- All Known Subinterfaces:
    `JdkMarshaller`
  All Known Implementing Classes:
    `AbstractMarshaller`, `AbstractNodeNameAwareMarshaller`, `JdkMarshallerImpl`

      public interface Marshaller

  `Marshaller` allows to marshal or unmarshal objects in grid. It provides serialization/deserialization mechanism for all instances that are sent across networks or are otherwise serialized.

  Ignite provides the following `Marshaller` implementations:

  - Default binary marshaller. Will be used when no other marshaller is explicitly set to the configuration. For more information, see `IgniteBinary`.
  - `JdkMarshaller`

  Below are examples of marshaller configuration, usage, and injection into tasks, jobs, and SPI's.

  ## Java Example

  `Marshaller` can be explicitly configured in code.

       JdkMarshaller marshaller = new JdkMarshaller();

       IgniteConfiguration cfg = new IgniteConfiguration();

       // Override marshaller.
       cfg.setMarshaller(marshaller);

       // Starts grid.
       G.start(cfg);

  ## Spring Example

  Marshaller can be configured from Spring XML configuration file:

       <bean id="grid.custom.cfg" class="org.apache.ignite.configuration.IgniteConfiguration" singleton="true">
           ...
           <property name="marshaller">
               <bean class="org.apache.ignite.marshaller.jdk.JdkMarshaller"/>
           </property>
           ...
       </bean>

  For information about Spring framework visit www.springframework.org

- - ### Method Summary

    All Methods Instance Methods Abstract Methods
    Modifier and Type | Method | Description
    --- | --- | ---
    `byte[]` | `marshal​(@Nullable Object obj)` | Marshals object to byte array.
    `void` | `marshal​(@Nullable Object obj, OutputStream out)` | Marshals object to the output stream.
    `void` | `nodeName​(@Nullable String nodeName)` | Set node name.
    `void` | `onUndeploy​(ClassLoader ldr)` | Undeployment callback invoked when class loader is being undeployed.
    `void` | `setContext​(MarshallerContext ctx)` | Sets marshaller context.
    `<T> T` | `unmarshal​(byte[] arr, @Nullable ClassLoader clsLdr)` | Unmarshals object from byte array using given class loader.
    `<T> T` | `unmarshal​(InputStream in, @Nullable ClassLoader clsLdr)` | Unmarshals object from the input stream using given class loader.

- - ### Method Detail

    - #### setContext

          void setContext​(MarshallerContext ctx)

      Sets marshaller context.
      Parameters:
        `ctx` - Marshaller context.

    - #### nodeName

          void nodeName​(@Nullable
                        @Nullable String nodeName)

      Set node name.
      Parameters:
        `nodeName` - Node name.

    - #### marshal

          void marshal​(@Nullable
                       @Nullable Object obj,
                       OutputStream out)
                throws IgniteCheckedException

      Marshals object to the output stream. This method should not close given output stream.
      Parameters:
        `obj` - Object to marshal. `null` object will be marshaled to binary `null` representation.
        `out` - Output stream to marshal into.
      Throws:
        `IgniteCheckedException` - If marshalling failed.

    - #### marshal

          byte[] marshal​(@Nullable
                         @Nullable Object obj)
                  throws IgniteCheckedException

      Marshals object to byte array.
      Parameters:
        `obj` - Object to marshal. `null` object will be marshaled to binary `null` representation.
      Returns:
        Byte array.
      Throws:
        `IgniteCheckedException` - If marshalling failed.

    - #### unmarshal

          <T> T unmarshal​(InputStream in,
                          @Nullable
                          @Nullable ClassLoader clsLdr)
                   throws IgniteCheckedException

      Unmarshals object from the input stream using given class loader. This method should not close given input stream.
      Type Parameters:
        `T` - Type of unmarshalled object.
      Parameters:
        `in` - Input stream.
        `clsLdr` - If not `null` then given class loader will be used for unmarshal object.
      Returns:
        Unmarshalled object.
      Throws:
        `IgniteCheckedException` - If unmarshalling failed.

    - #### unmarshal

          <T> T unmarshal​(byte[] arr,
                          @Nullable
                          @Nullable ClassLoader clsLdr)
                   throws IgniteCheckedException

      Unmarshals object from byte array using given class loader.
      Type Parameters:
        `T` - Type of unmarshalled object.
      Parameters:
        `arr` - Byte array.
        `clsLdr` - If not `null` then given class loader will be used for unmarshal object.
      Returns:
        Unmarshalled object.
      Throws:
        `IgniteCheckedException` - If unmarshalling failed.

    - #### onUndeploy

          void onUndeploy​(ClassLoader ldr)

      Undeployment callback invoked when class loader is being undeployed. Some marshallers may want to clean their internal state that uses the undeployed class loader somehow.
      Parameters:
        `ldr` - Class loader being undeployed.