org.springframework.remoting.httpinvoker
Class AbstractHttpInvokerRequestExecutor

java.lang.Object
  org.springframework.remoting.httpinvoker.AbstractHttpInvokerRequestExecutor

All Implemented Interfaces:

BeanClassLoaderAware, HttpInvokerRequestExecutor

Direct Known Subclasses:

CommonsHttpInvokerRequestExecutor, SimpleHttpInvokerRequestExecutor

public abstract class AbstractHttpInvokerRequestExecutor
extends Object
implements HttpInvokerRequestExecutor, BeanClassLoaderAware

Abstract base implementation of the HttpInvokerRequestExecutor interface.

Pre-implements serialization of RemoteInvocation objects and deserialization of RemoteInvocationResults objects.

Since:

1.1

Author:

Juergen Hoeller

See Also:

doExecuteRequest(org.springframework.remoting.httpinvoker.HttpInvokerClientConfiguration, java.io.ByteArrayOutputStream)

Field Summary

static String	CONTENT_TYPE_SERIALIZED_OBJECT Default content type: "application/x-java-serialized-object"
protected static String	ENCODING_GZIP
protected static String	HTTP_HEADER_ACCEPT_ENCODING
protected static String	HTTP_HEADER_CONTENT_ENCODING
protected static String	HTTP_HEADER_CONTENT_LENGTH
protected static String	HTTP_HEADER_CONTENT_TYPE
protected static String	HTTP_METHOD_POST
protected Log	logger

Constructor Summary

AbstractHttpInvokerRequestExecutor()

Method Summary

protected ObjectInputStream	createObjectInputStream(InputStream is, String codebaseUrl) Create an ObjectInputStream for the given InputStream and codebase.
protected InputStream	decorateInputStream(InputStream is) Return the InputStream to use for reading remote invocation results, potentially decorating the given original InputStream.
protected OutputStream	decorateOutputStream(OutputStream os) Return the OutputStream to use for writing remote invocations, potentially decorating the given original OutputStream.
protected abstract RemoteInvocationResult	doExecuteRequest(HttpInvokerClientConfiguration config, ByteArrayOutputStream baos) Execute a request to send the given serialized remote invocation.
protected RemoteInvocationResult	doReadRemoteInvocationResult(ObjectInputStream ois) Perform the actual reading of an invocation object from the given ObjectInputStream.
protected void	doWriteRemoteInvocation(RemoteInvocation invocation, ObjectOutputStream oos) Perform the actual writing of the given invocation object to the given ObjectOutputStream.
RemoteInvocationResult	executeRequest(HttpInvokerClientConfiguration config, RemoteInvocation invocation) Execute a request to send the given remote invocation.
protected ClassLoader	getBeanClassLoader() Return the bean ClassLoader that this executor is supposed to use.
protected ByteArrayOutputStream	getByteArrayOutputStream(RemoteInvocation invocation) Serialize the given RemoteInvocation into a ByteArrayOutputStream.
String	getContentType() Return the content type to use for sending HTTP invoker requests.
boolean	isAcceptGzipEncoding() Return whether to accept GZIP encoding, that is, whether to send the HTTP "Accept-Encoding" header with "gzip" as value.
protected RemoteInvocationResult	readRemoteInvocationResult(InputStream is, String codebaseUrl) Deserialize a RemoteInvocationResult object from the given InputStream.
void	setAcceptGzipEncoding(boolean acceptGzipEncoding) Set whether to accept GZIP encoding, that is, whether to send the HTTP "Accept-Encoding" header with "gzip" as value.
void	setBeanClassLoader(ClassLoader classLoader) Callback that supplies the bean class loader to a bean instance.
void	setContentType(String contentType) Specify the content type to use for sending HTTP invoker requests.
protected void	writeRemoteInvocation(RemoteInvocation invocation, OutputStream os) Serialize the given RemoteInvocation to the given OutputStream.

Methods inherited from class java.lang.Object

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

Field Detail

CONTENT_TYPE_SERIALIZED_OBJECT

public static final String CONTENT_TYPE_SERIALIZED_OBJECT

Default content type: "application/x-java-serialized-object"

See Also:

Constant Field Values

HTTP_METHOD_POST

protected static final String HTTP_METHOD_POST

See Also:

Constant Field Values

HTTP_HEADER_CONTENT_TYPE

protected static final String HTTP_HEADER_CONTENT_TYPE

See Also:

Constant Field Values

HTTP_HEADER_CONTENT_LENGTH

protected static final String HTTP_HEADER_CONTENT_LENGTH

See Also:

Constant Field Values

HTTP_HEADER_ACCEPT_ENCODING

protected static final String HTTP_HEADER_ACCEPT_ENCODING

See Also:

Constant Field Values

HTTP_HEADER_CONTENT_ENCODING

protected static final String HTTP_HEADER_CONTENT_ENCODING

See Also:

Constant Field Values

ENCODING_GZIP

protected static final String ENCODING_GZIP

See Also:

Constant Field Values

logger

protected final Log logger

Constructor Detail

AbstractHttpInvokerRequestExecutor

public AbstractHttpInvokerRequestExecutor()

Method Detail

setContentType

public void setContentType(String contentType)

Specify the content type to use for sending HTTP invoker requests.

Default is "application/x-java-serialized-object".

getContentType

public String getContentType()

Return the content type to use for sending HTTP invoker requests.

setAcceptGzipEncoding

public void setAcceptGzipEncoding(boolean acceptGzipEncoding)

Set whether to accept GZIP encoding, that is, whether to send the HTTP "Accept-Encoding" header with "gzip" as value.

Default is "true". Turn this flag off if you do not want GZIP response compression even if enabled on the HTTP server.

isAcceptGzipEncoding

public boolean isAcceptGzipEncoding()

Return whether to accept GZIP encoding, that is, whether to send the HTTP "Accept-Encoding" header with "gzip" as value.

setBeanClassLoader

public void setBeanClassLoader(ClassLoader classLoader)

Description copied from interface: BeanClassLoaderAware

Callback that supplies the bean class loader to a bean instance.

Invoked after the population of normal bean properties but before an initialization callback such as InitializingBean's InitializingBean.afterPropertiesSet() method or a custom init-method.

Specified by:

setBeanClassLoader in interface BeanClassLoaderAware

Parameters:

classLoader - the owning class loader; may be null in which case a default ClassLoader must be used, for example the ClassLoader obtained via ClassUtils.getDefaultClassLoader()

getBeanClassLoader

protected ClassLoader getBeanClassLoader()

Return the bean ClassLoader that this executor is supposed to use.

executeRequest

public final RemoteInvocationResult executeRequest(HttpInvokerClientConfiguration config,
                                                   RemoteInvocation invocation)
                                            throws Exception

Description copied from interface: HttpInvokerRequestExecutor

Execute a request to send the given remote invocation.

Specified by:

executeRequest in interface HttpInvokerRequestExecutor

Parameters:

config - the HTTP invoker configuration that specifies the target service

invocation - the RemoteInvocation to execute

Returns:

the RemoteInvocationResult object

Throws:

IOException - if thrown by I/O operations

ClassNotFoundException - if thrown during deserialization

Exception - in case of general errors

getByteArrayOutputStream

protected ByteArrayOutputStream getByteArrayOutputStream(RemoteInvocation invocation)
                                                  throws IOException

Serialize the given RemoteInvocation into a ByteArrayOutputStream.

Parameters:

invocation - the RemoteInvocation object

Returns:

a ByteArrayOutputStream with the serialized RemoteInvocation

Throws:

IOException - if thrown by I/O methods

writeRemoteInvocation

protected void writeRemoteInvocation(RemoteInvocation invocation,
                                     OutputStream os)
                              throws IOException

Serialize the given RemoteInvocation to the given OutputStream.

The default implementation gives decorateOutputStream a chance to decorate the stream first (for example, for custom encryption or compression). Creates an ObjectOutputStream for the final stream and calls doWriteRemoteInvocation to actually write the object.

Can be overridden for custom serialization of the invocation.

Parameters:

invocation - the RemoteInvocation object

os - the OutputStream to write to

Throws:

IOException - if thrown by I/O methods

See Also:

decorateOutputStream(java.io.OutputStream), doWriteRemoteInvocation(org.springframework.remoting.support.RemoteInvocation, java.io.ObjectOutputStream)

decorateOutputStream

protected OutputStream decorateOutputStream(OutputStream os)
                                     throws IOException

Return the OutputStream to use for writing remote invocations, potentially decorating the given original OutputStream.

The default implementation returns the given stream as-is. Can be overridden, for example, for custom encryption or compression.

Parameters:

os - the original OutputStream

Returns:

the potentially decorated OutputStream

Throws:

IOException

doWriteRemoteInvocation

protected void doWriteRemoteInvocation(RemoteInvocation invocation,
                                       ObjectOutputStream oos)
                                throws IOException

Perform the actual writing of the given invocation object to the given ObjectOutputStream.

The default implementation simply calls writeObject. Can be overridden for serialization of a custom wrapper object rather than the plain invocation, for example an encryption-aware holder.

Parameters:

invocation - the RemoteInvocation object

oos - the ObjectOutputStream to write to

Throws:

IOException - if thrown by I/O methods

See Also:

ObjectOutputStream.writeObject(java.lang.Object)

doExecuteRequest

protected abstract RemoteInvocationResult doExecuteRequest(HttpInvokerClientConfiguration config,
                                                           ByteArrayOutputStream baos)
                                                    throws Exception

Execute a request to send the given serialized remote invocation.

Implementations will usually call readRemoteInvocationResult to deserialize a returned RemoteInvocationResult object.

Parameters:

config - the HTTP invoker configuration that specifies the target service

baos - the ByteArrayOutputStream that contains the serialized RemoteInvocation object

Returns:

the RemoteInvocationResult object

Throws:

IOException - if thrown by I/O operations

ClassNotFoundException - if thrown during deserialization

Exception - in case of general errors

See Also:

readRemoteInvocationResult(java.io.InputStream, String)

readRemoteInvocationResult

protected RemoteInvocationResult readRemoteInvocationResult(InputStream is,
                                                            String codebaseUrl)
                                                     throws IOException,
                                                            ClassNotFoundException

Deserialize a RemoteInvocationResult object from the given InputStream.

Gives decorateInputStream a chance to decorate the stream first (for example, for custom encryption or compression). Creates an ObjectInputStream via createObjectInputStream and calls doReadRemoteInvocationResult to actually read the object.

Can be overridden for custom serialization of the invocation.

Parameters:

is - the InputStream to read from

codebaseUrl - the codebase URL to load classes from if not found locally

Returns:

the RemoteInvocationResult object

Throws:

IOException - if thrown by I/O methods

ClassNotFoundException - if thrown during deserialization

See Also:

decorateInputStream(java.io.InputStream), createObjectInputStream(java.io.InputStream, java.lang.String), doReadRemoteInvocationResult(java.io.ObjectInputStream)

decorateInputStream

protected InputStream decorateInputStream(InputStream is)
                                   throws IOException

Return the InputStream to use for reading remote invocation results, potentially decorating the given original InputStream.

The default implementation returns the given stream as-is. Can be overridden, for example, for custom encryption or compression.

Parameters:

is - the original InputStream

Returns:

the potentially decorated InputStream

Throws:

IOException

createObjectInputStream

protected ObjectInputStream createObjectInputStream(InputStream is,
                                                    String codebaseUrl)
                                             throws IOException

Create an ObjectInputStream for the given InputStream and codebase. The default implementation creates a CodebaseAwareObjectInputStream.

Spring's CodebaseAwareObjectInputStream is not only used for loading from a specified codebase, but also to explicitly resolve primitive class names. This is done by the standard ObjectInputStream on JDK 1.4+, but needs to be done explicitly on JDK 1.3.

Parameters:

is - the InputStream to read from

codebaseUrl - the codebase URL to load classes from if not found locally (can be null)

Returns:

the new ObjectInputStream instance to use

Throws:

IOException - if creation of the ObjectInputStream failed

See Also:

CodebaseAwareObjectInputStream

doReadRemoteInvocationResult

protected RemoteInvocationResult doReadRemoteInvocationResult(ObjectInputStream ois)
                                                       throws IOException,
                                                              ClassNotFoundException

Perform the actual reading of an invocation object from the given ObjectInputStream.

The default implementation simply calls readObject. Can be overridden for deserialization of a custom wrapper object rather than the plain invocation, for example an encryption-aware holder.

Parameters:

ois - the ObjectInputStream to read from

Returns:

the RemoteInvocationResult object

Throws:

IOException - if thrown by I/O methods

ClassNotFoundException

See Also:

ObjectOutputStream.writeObject(java.lang.Object)