@InterfaceAudience.Private public abstract class FileSystemReleaseFilter extends Object implements javax.servlet.Filter
FileSystemReleaseFilter releases back to the
FileSystemAccess service a FileSystem instance.
This filter is useful in situations where a servlet request is streaming out HDFS data and the corresponding filesystem instance have to be closed after the streaming completes.
| Constructor and Description |
|---|
FileSystemReleaseFilter() |
| Modifier and Type | Method and Description |
|---|---|
void |
destroy()
Destroys the filter.
|
void |
doFilter(javax.servlet.ServletRequest servletRequest,
javax.servlet.ServletResponse servletResponse,
javax.servlet.FilterChain filterChain)
It delegates the incoming request to the
FilterChain, and
at its completion (in a finally block) releases the filesystem instance
back to the FileSystemAccess service. |
protected abstract FileSystemAccess |
getFileSystemAccess()
Abstract method to be implemented by concrete implementations of the
filter that return the
FileSystemAccess service to which the filesystem
will be returned to. |
void |
init(javax.servlet.FilterConfig filterConfig)
Initializes the filter.
|
static void |
setFileSystem(org.apache.hadoop.fs.FileSystem fs)
Static method that sets the
FileSystem to release back to
the FileSystemAccess service on servlet request completion. |
public void init(javax.servlet.FilterConfig filterConfig)
throws javax.servlet.ServletException
This implementation is a NOP.
init in interface javax.servlet.FilterfilterConfig - filter configuration.javax.servlet.ServletException - thrown if the filter could not be initialized.public void doFilter(javax.servlet.ServletRequest servletRequest,
javax.servlet.ServletResponse servletResponse,
javax.servlet.FilterChain filterChain)
throws IOException,
javax.servlet.ServletException
FilterChain, and
at its completion (in a finally block) releases the filesystem instance
back to the FileSystemAccess service.doFilter in interface javax.servlet.FilterservletRequest - servlet request.servletResponse - servlet response.filterChain - filter chain.IOException - thrown if an IO error occurs.javax.servlet.ServletException - thrown if a servlet error occurs.public void destroy()
This implementation is a NOP.
destroy in interface javax.servlet.Filterpublic static void setFileSystem(org.apache.hadoop.fs.FileSystem fs)
FileSystem to release back to
the FileSystemAccess service on servlet request completion.fs - a filesystem instance.protected abstract FileSystemAccess getFileSystemAccess()
FileSystemAccess service to which the filesystem
will be returned to.Copyright © 2008–2024 Apache Software Foundation. All rights reserved.