javax.portlet
Interface RenderResponse

All Superinterfaces:

PortletResponse

public interface RenderResponse

extends PortletResponse

The RenderResponse defines an object to assist a portlet in sending a response to the portal. The portlet container creates a RenderResponse object and passes it as an argument to the render method of the portlet.

See the Internet RFCs such as RFC 2045 for more information on MIME.

See Also:

RenderRequest, PortletResponse

Field Summary

static java.lang.String

EXPIRATION_CACHE Property to set the expiration time in seconds for this response using the setProperty method.

Method Summary

PortletURL	createActionURL() Creates a portlet URL pointing to the current portlet mode and current window state, triggering an action request and a render request.
PortletURL	createRenderURL() Creates a portlet URL pointing to the current portlet mode and current window state, triggering a render call.
java.lang.String	encodeNamespace(java.lang.String aValue) Maps the given string value into this portlet namespace and therefore ensures the uniqueness of the string value in the whole portal page.
void	flushBuffer() Forces any content in the buffer to be written to the client.
int	getBufferSize() Returns the actual buffer size used for the response.
java.lang.String	getCharacterEncoding() Returns the name of the charset used for the MIME body sent in this response.
java.lang.String	getContentType() Returns the MIME type that can be used to contribute markup to the render response.
java.util.Locale	getLocale() Returns the locale assigned to the response.
java.io.OutputStream	getPortletOutputStream() Returns a OutputStream suitable for writing binary data in the response.
java.io.PrintWriter	getWriter() Returns a PrintWriter object that can send character text to the portal.
boolean	isCommitted() Returns a boolean indicating if the response has been committed.
void	reset() Clears any data that exists in the buffer as well as the properties set.
void	resetBuffer() Clears the content of the underlying buffer in the response without clearing properties set.
void	setBufferSize(int size) Sets the preferred buffer size for the body of the response.
void	setContentType(java.lang.String type) Sets the MIME type for the render response.
void	setTitle(java.lang.String title) This method can be called to set the title of a portlet.

Methods inherited from interface javax.portlet.PortletResponse

addProperty, encodeURL, setProperty

Field Detail

EXPIRATION_CACHE

public static final java.lang.String EXPIRATION_CACHE

Property to set the expiration time in seconds for this response using the setProperty method.

If the expiration value is set to 0, caching is disabled for this portlet; if the value is set to -1, the cache does not expire.

The value is "portlet.expiration-cache".

Method Detail

getContentType

public java.lang.String getContentType()

Returns the MIME type that can be used to contribute markup to the render response.

If no content type was set previously using the setContentType(java.lang.String) method this method retuns null.

Returns:

the MIME type of the response, or null if no content type is set

See Also:

setContentType(java.lang.String)

createRenderURL

public PortletURL createRenderURL()

Creates a portlet URL pointing to the current portlet mode and current window state, triggering a render call. The returned URL can be further extended by adding portlet-specific parameters and portlet modes and window states.

The created URL will per default not contain any parameters of the current render request.

Returns:

a portlet render URL

createActionURL

public PortletURL createActionURL()

Creates a portlet URL pointing to the current portlet mode and current window state, triggering an action request and a render request. The returned URL can be further extended by adding portlet-specific parameters and portlet modes and window states.

The created URL will per default not contain any parameters of the current render request.

Returns:

a portlet action URL

encodeNamespace

public java.lang.String encodeNamespace(java.lang.String aValue)

Maps the given string value into this portlet namespace and therefore ensures the uniqueness of the string value in the whole portal page. This method should be applied to every variable or name used in the output stream. For example a function name in javascript.

If the string passed to the encodeNamespace method must be a valid identifier as defined in the 3.8 Identifier Section of the Java Language Specification Second Edition, the returned string is also a valid identifier.

If null is passed as value this method returns the portlet namespace.

Parameters:

aValue - the name to be mapped

Returns:

the mapped name

setTitle

public void setTitle(java.lang.String title)

This method can be called to set the title of a portlet.

The value can be either a text String or a resource URI.

Parameters:

title - portlet title as text String or resource URI

setContentType

public void setContentType(java.lang.String type)

Sets the MIME type for the render response. The portlet must set the content type before calling getWriter() or getPortletOutputStream().

Calling setContentType after getWriter or getOutputStream does not change the content type.

Parameters:

type - the content MIME type

Throws:

java.lang.IllegalArgumentException - if the given type is not in the list returned by PortletRequest.getResponseContentTypes

See Also:

PortletRequest.getResponseContentTypes(), getContentType()

getCharacterEncoding

public java.lang.String getCharacterEncoding()

Returns the name of the charset used for the MIME body sent in this response.

See RFC 2047 (http://ds.internic.net/rfc/rfc2045.txt) for more information about character encoding and MIME.

Returns:

a String specifying the name of the charset, for example, ISO-8859-1

getWriter

public java.io.PrintWriter getWriter()
                              throws java.io.IOException

Returns a PrintWriter object that can send character text to the portal.

Before calling this method the content type of the render response must be set using the setContentType(java.lang.String) method.

Either this method or getPortletOutputStream() may be called to write the body, not both.

Returns:

a PrintWriter object that can return character data to the portal

Throws:

java.io.IOException - if an input or output exception occurred

java.lang.IllegalStateException - if the getPortletOutputStream method has been called on this response, or if no content type was set using the setContentType method.

See Also:

setContentType(java.lang.String), getPortletOutputStream()

getLocale

public java.util.Locale getLocale()

Returns the locale assigned to the response.

Returns:

Locale of this response

setBufferSize

public void setBufferSize(int size)

Sets the preferred buffer size for the body of the response. The portlet container will use a buffer at least as large as the size requested.

This method must be called before any response body content is written; if content has been written, or the portlet container does not support buffering, this method throws an IllegalStateException.

Parameters:

size - the preferred buffer size

Throws:

java.lang.IllegalStateException - if this method is called after content has been written, or the portlet container does not support buffering

See Also:

getBufferSize(), flushBuffer(), isCommitted(), reset()

getBufferSize

public int getBufferSize()

Returns the actual buffer size used for the response. If no buffering is used, this method returns 0.

Depending on the portlet container implementation the buffer may be shared by serveral portlets.

Returns:

the actual buffer size used

See Also:

setBufferSize(int), flushBuffer(), isCommitted(), reset()

flushBuffer

public void flushBuffer()
                 throws java.io.IOException

Forces any content in the buffer to be written to the client. A call to this method automatically commits the response.

Throws:

java.io.IOException - if an error occured when writing the output

See Also:

setBufferSize(int), getBufferSize(), isCommitted(), reset()

resetBuffer

public void resetBuffer()

Clears the content of the underlying buffer in the response without clearing properties set. If the response has been committed, this method throws an IllegalStateException.

Throws:

IllegalStateException - if this method is called after response is comitted

See Also:

setBufferSize(int), getBufferSize(), isCommitted(), reset()

isCommitted

public boolean isCommitted()

Returns a boolean indicating if the response has been committed.

Returns:

a boolean indicating if the response has been committed

See Also:

setBufferSize(int), getBufferSize(), flushBuffer(), reset()

reset

public void reset()

Clears any data that exists in the buffer as well as the properties set. If the response has been committed, this method throws an IllegalStateException.

Throws:

java.lang.IllegalStateException - if the response has already been committed

See Also:

setBufferSize(int), getBufferSize(), flushBuffer(), isCommitted()

getPortletOutputStream

public java.io.OutputStream getPortletOutputStream()
                                            throws java.io.IOException

Returns a OutputStream suitable for writing binary data in the response. The portlet container does not encode the binary data.

Before calling this method the content type of the render response must be set using the setContentType(java.lang.String) method.

Calling flush() on the OutputStream commits the response.

Either this method or getWriter() may be called to write the body, not both.

Returns:

a OutputStream for writing binary data

Throws:

java.lang.IllegalStateException - if the getWriter method has been called on this response, or if no content type was set using the setContentType method.

java.io.IOException - if an input or output exception occurred

See Also:

setContentType(java.lang.String), getWriter()