Package org.apache.catalina.servlets

Class DefaultServlet

java.lang.Object
javax.servlet.GenericServlet
javax.servlet.http.HttpServlet
org.apache.catalina.servlets.DefaultServlet
All Implemented Interfaces:
Serializable, Servlet, ServletConfig
Direct Known Subclasses:
WebdavServlet
public class DefaultServlet extends HttpServlet

The default resource-serving servlet for most web applications, used to serve static resources such as HTML pages and images.

This servlet is intended to be mapped to / e.g.: 

   <servlet-mapping>
       <servlet-name>default</servlet-name>
       <url-pattern>/</url-pattern>
   </servlet-mapping>

It can be mapped to sub-paths, however in all cases resources are served from the web application resource root using the full path from the root of the web application context.
e.g. given a web application structure: 

 /context
   /images
     tomcat2.jpg
   /static
     /images
       tomcat.jpg

... and a servlet mapping that maps only /static/* to the default servlet: 

   <servlet-mapping>
       <servlet-name>default</servlet-name>
       <url-pattern>/static/*</url-pattern>
   </servlet-mapping>

Then a request to /context/static/images/tomcat.jpg will succeed while a request to /context/images/tomcat2.jpg will fail.

Author:
Craig R. McClanahan, Remy Maucherat
See Also:

  • Field Details

    • sm

      protected static final StringManager sm
      The string manager for this package.

    • FULL

      protected static final ArrayList<DefaultServlet.Range> FULL
      Full range marker.

    • mimeSeparation

      protected static final String mimeSeparation
      MIME multipart separation string
      See Also:

    • RESOURCES_JNDI_NAME

      @Deprecated protected static final String RESOURCES_JNDI_NAME
      Deprecated.
      Unused. Will be removed in Tomcat 9.
      JNDI resources name.
      See Also:

    • BUFFER_SIZE

      protected static final int BUFFER_SIZE
      Size of file transfer buffer in bytes.
      See Also:

    • debug

      protected int debug
      The debugging detail level for this servlet.

    • input

      protected int input
      The input buffer size to use when serving resources.

    • listings

      protected boolean listings
      Should we generate directory listings?

    • readOnly

      protected boolean readOnly
      Read only flag. By default, it's set to true.

    • compressionFormats

      protected DefaultServlet.CompressionFormat[] compressionFormats
      List of compression formats to serve and their preference order.

    • output

      protected int output
      The output buffer size to use when serving resources.

    • localXsltFile

      protected String localXsltFile
      Allow customized directory listing per directory.

    • contextXsltFile

      protected String contextXsltFile
      Allow customized directory listing per context.

    • globalXsltFile

      protected String globalXsltFile
      Allow customized directory listing per instance.

    • readmeFile

      protected String readmeFile
      Allow a readme file to be included.

    • resources

      protected transient WebResourceRoot resources
      The complete set of web application resources

    • fileEncoding

      protected String fileEncoding
      File encoding to be used when reading static files. If none is specified the platform default is used.

    • sendfileSize

      protected int sendfileSize
      Minimum size for sendfile usage in bytes.

    • useAcceptRanges

      protected boolean useAcceptRanges
      Should the Accept-Ranges: bytes header be send with static resources?

    • showServerInfo

      protected boolean showServerInfo
      Flag to determine if server information is presented.

    • sortListings

      protected boolean sortListings
      Flag to determine if resources should be sorted.

    • sortManager

      protected transient org.apache.catalina.servlets.DefaultServlet.SortManager sortManager
      The sorting manager for sorting files and directories.

  • Constructor Details

    • DefaultServlet

      public DefaultServlet()

  • Method Details

    • destroy

      public void destroy()
      Finalize this servlet.
      Specified by:
      destroy in interface Servlet
      Overrides:
      destroy in class GenericServlet

    • init

      public void init() throws ServletException
      Initialize this servlet.
      Overrides:
      init in class GenericServlet
      Throws:
      ServletException - if an exception occurs that interrupts the servlet's normal operation

    • getRelativePath

      protected String getRelativePath(HttpServletRequest request)
      Return the relative path associated with this servlet.
      Parameters:
      request - The servlet request we are processing
      Returns:
      the relative path

    • getRelativePath

      protected String getRelativePath(HttpServletRequest request, boolean allowEmptyPath)

    • getPathPrefix

      protected String getPathPrefix(HttpServletRequest request)
      Determines the appropriate path to prepend resources with when generating directory listings. Depending on the behaviour of getRelativePath(HttpServletRequest) this will change.
      Parameters:
      request - the request to determine the path for
      Returns:
      the prefix to apply to all resources in the listing.

    • service

      protected void service(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException
      Description copied from class: javax.servlet.http.HttpServlet
      Receives standard HTTP requests from the public service method and dispatches them to the doMethod methods defined in this class. This method is an HTTP-specific version of the Servlet.service(javax.servlet.ServletRequest, javax.servlet.ServletResponse) method. There's no need to override this method.
      Overrides:
      service in class HttpServlet
      Parameters:
      req - the HttpServletRequest object that contains the request the client made of the servlet
      resp - the HttpServletResponse object that contains the response the servlet returns to the client
      Throws:
      ServletException - if the HTTP request cannot be handled
      IOException - if an input or output error occurs while the servlet is handling the HTTP request
      See Also:

    • doGet

      protected void doGet(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException
      Process a GET request for the specified resource.
      Overrides:
      doGet in class HttpServlet
      Parameters:
      request - The servlet request we are processing
      response - The servlet response we are creating
      Throws:
      IOException - if an input/output error occurs
      ServletException - if a servlet-specified error occurs
      See Also:

    • doHead

      protected void doHead(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException
      Process a HEAD request for the specified resource.
      Overrides:
      doHead in class HttpServlet
      Parameters:
      request - The servlet request we are processing
      response - The servlet response we are creating
      Throws:
      IOException - if an input/output error occurs
      ServletException - if a servlet-specified error occurs

    • doOptions

      protected void doOptions(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException
      Override default implementation to ensure that TRACE is correctly handled.
      Overrides:
      doOptions in class HttpServlet
      Parameters:
      req - the HttpServletRequest object that contains the request the client made of the servlet
      resp - the HttpServletResponse object that contains the response the servlet returns to the client
      Throws:
      IOException - if an input or output error occurs while the servlet is handling the OPTIONS request
      ServletException - if the request for the OPTIONS cannot be handled

    • determineMethodsAllowed

      protected String determineMethodsAllowed(HttpServletRequest req)

    • sendNotAllowed

      protected void sendNotAllowed(HttpServletRequest req, HttpServletResponse resp) throws IOException
      Throws:
      IOException

    • doPost

      protected void doPost(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException
      Process a POST request for the specified resource.
      Overrides:
      doPost in class HttpServlet
      Parameters:
      request - The servlet request we are processing
      response - The servlet response we are creating
      Throws:
      IOException - if an input/output error occurs
      ServletException - if a servlet-specified error occurs
      See Also:

    • doPut

      protected void doPut(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException
      Process a PUT request for the specified resource.
      Overrides:
      doPut in class HttpServlet
      Parameters:
      req - The servlet request we are processing
      resp - The servlet response we are creating
      Throws:
      IOException - if an input/output error occurs
      ServletException - if a servlet-specified error occurs

    • executePartialPut

      protected File executePartialPut(HttpServletRequest req, DefaultServlet.Range range, String path) throws IOException
      Handle a partial PUT. New content specified in request is appended to existing content in oldRevisionContent (if present). This code does not support simultaneous partial updates to the same resource.
      Parameters:
      req - The Servlet request
      range - The range that will be written
      path - The path
      Returns:
      the associated file object
      Throws:
      IOException - an IO error occurred

    • doDelete

      protected void doDelete(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException
      Process a DELETE request for the specified resource.
      Overrides:
      doDelete in class HttpServlet
      Parameters:
      req - The servlet request we are processing
      resp - The servlet response we are creating
      Throws:
      IOException - if an input/output error occurs
      ServletException - if a servlet-specified error occurs

    • checkIfHeaders

      protected boolean checkIfHeaders(HttpServletRequest request, HttpServletResponse response, WebResource resource) throws IOException
      Check if the conditions specified in the optional If headers are satisfied.
      Parameters:
      request - The servlet request we are processing
      response - The servlet response we are creating
      resource - The resource
      Returns:
      true if the resource meets all the specified conditions, and false if any of the conditions is not satisfied, in which case request processing is stopped
      Throws:
      IOException - an IO error occurred

    • rewriteUrl

      protected String rewriteUrl(String path)
      URL rewriter.
      Parameters:
      path - Path which has to be rewritten
      Returns:
      the rewritten path

    • serveResource

      protected void serveResource(HttpServletRequest request, HttpServletResponse response, boolean content, String inputEncoding) throws IOException, ServletException
      Serve the specified resource, optionally including the data content.
      Parameters:
      request - The servlet request we are processing
      response - The servlet response we are creating
      content - Should the content be included?
      inputEncoding - The encoding to use if it is necessary to access the source as characters rather than as bytes
      Throws:
      IOException - if an input/output error occurs
      ServletException - if a servlet-specified error occurs

    • parseContentRange

      protected DefaultServlet.Range parseContentRange(HttpServletRequest request, HttpServletResponse response) throws IOException
      Parse the content-range header.
      Parameters:
      request - The servlet request we are processing
      response - The servlet response we are creating
      Returns:
      the partial content-range, null if the content-range header was invalid or #IGNORE if there is no header to process
      Throws:
      IOException - an IO error occurred

    • parseRange

      protected ArrayList<DefaultServlet.Range> parseRange(HttpServletRequest request, HttpServletResponse response, WebResource resource) throws IOException
      Parse the range header.
      Parameters:
      request - The servlet request we are processing
      response - The servlet response we are creating
      resource - The resource
      Returns:
      a list of ranges, null if the range header was invalid or #FULL if the Range header should be ignored.
      Throws:
      IOException - an IO error occurred

    • render

      @Deprecated protected InputStream render(String contextPath, WebResource resource) throws IOException, ServletException
      Deprecated.
      Unused. Will be removed in Tomcat 9
      Decide which way to render. HTML or XML.
      Parameters:
      contextPath - The path
      resource - The resource
      Returns:
      the input stream with the rendered output
      Throws:
      IOException - an IO error occurred
      ServletException - rendering error

    • render

      @Deprecated protected InputStream render(String contextPath, WebResource resource, String encoding) throws IOException, ServletException
      Deprecated.
      Use render(HttpServletRequest, String, WebResource, String) instead
      Decide which way to render. HTML or XML.
      Parameters:
      contextPath - The path
      resource - The resource
      encoding - The encoding to use to process the readme (if any)
      Returns:
      the input stream with the rendered output
      Throws:
      IOException - an IO error occurred
      ServletException - rendering error

    • render

      protected InputStream render(HttpServletRequest request, String contextPath, WebResource resource, String encoding) throws IOException, ServletException
      Decide which way to render. HTML or XML.
      Parameters:
      request - The HttpServletRequest being served
      contextPath - The path
      resource - The resource
      encoding - The encoding to use to process the readme (if any)
      Returns:
      the input stream with the rendered output
      Throws:
      IOException - an IO error occurred
      ServletException - rendering error

    • renderXml

      @Deprecated protected InputStream renderXml(String contextPath, WebResource resource, Source xsltSource) throws IOException, ServletException
      Deprecated.
      Unused. Will be removed in Tomcat 9
      Return an InputStream to an XML representation of the contents this directory.
      Parameters:
      contextPath - Context path to which our internal paths are relative
      resource - The associated resource
      xsltSource - The XSL stylesheet
      Returns:
      the XML data
      Throws:
      IOException - an IO error occurred
      ServletException - rendering error

    • renderXml

      @Deprecated protected InputStream renderXml(String contextPath, WebResource resource, Source xsltSource, String encoding) throws ServletException, IOException
      Deprecated.
      Unused. Will be removed in Tomcat 10
      Return an InputStream to an XML representation of the contents this directory.
      Parameters:
      contextPath - Context path to which our internal paths are relative
      resource - The associated resource
      xsltSource - The XSL stylesheet
      encoding - The encoding to use to process the readme (if any)
      Returns:
      the XML data
      Throws:
      IOException - an IO error occurred
      ServletException - rendering error

    • renderXml

      protected InputStream renderXml(HttpServletRequest request, String contextPath, WebResource resource, Source xsltSource, String encoding) throws IOException, ServletException
      Return an InputStream to an XML representation of the contents this directory.
      Parameters:
      request - The HttpServletRequest being served
      contextPath - Context path to which our internal paths are relative
      resource - The associated resource
      xsltSource - The XSL stylesheet
      encoding - The encoding to use to process the readme (if any)
      Returns:
      the XML data
      Throws:
      IOException - an IO error occurred
      ServletException - rendering error

    • renderHtml

      @Deprecated protected InputStream renderHtml(String contextPath, WebResource resource) throws IOException
      Deprecated.
      Unused. Will be removed in Tomcat 9
      Return an InputStream to an HTML representation of the contents of this directory.
      Parameters:
      contextPath - Context path to which our internal paths are relative
      resource - The associated resource
      Returns:
      the HTML data
      Throws:
      IOException - an IO error occurred

    • renderHtml

      @Deprecated protected InputStream renderHtml(String contextPath, WebResource resource, String encoding) throws IOException
      Deprecated.
      Unused. Will be removed in Tomcat 10
      Return an InputStream to an HTML representation of the contents of this directory.
      Parameters:
      contextPath - Context path to which our internal paths are relative
      resource - The associated resource
      encoding - The encoding to use to process the readme (if any)
      Returns:
      the HTML data
      Throws:
      IOException - an IO error occurred

    • renderHtml

      protected InputStream renderHtml(HttpServletRequest request, String contextPath, WebResource resource, String encoding) throws IOException
      Return an InputStream to an HTML representation of the contents of this directory.
      Parameters:
      request - The HttpServletRequest being served
      contextPath - Context path to which our internal paths are relative
      resource - The associated resource
      encoding - The encoding to use to process the readme (if any)
      Returns:
      the HTML data
      Throws:
      IOException - an IO error occurred

    • renderSize

      protected String renderSize(long size)
      Render the specified file size (in bytes).
      Parameters:
      size - File size (in bytes)
      Returns:
      the formatted size

    • getReadme

      @Deprecated protected String getReadme(WebResource directory)
      Deprecated.
      Unused. Will be removed in Tomcat 9
      Get the readme file as a string.
      Parameters:
      directory - The directory to search
      Returns:
      the readme for the specified directory

    • getReadme

      protected String getReadme(WebResource directory, String encoding)
      Get the readme file as a string.
      Parameters:
      directory - The directory to search
      encoding - The readme encoding
      Returns:
      the readme for the specified directory

    • findXsltSource

      protected Source findXsltSource(WebResource directory) throws IOException
      Return a Source for the xsl template (if possible).
      Parameters:
      directory - The directory to search
      Returns:
      the source for the specified directory
      Throws:
      IOException - an IO error occurred

    • checkSendfile

      protected boolean checkSendfile(HttpServletRequest request, HttpServletResponse response, WebResource resource, long length, DefaultServlet.Range range)
      Check if sendfile can be used.
      Parameters:
      request - The Servlet request
      response - The Servlet response
      resource - The resource
      length - The length which will be written (will be used only if range is null)
      range - The range that will be written
      Returns:
      true if sendfile should be used (writing is then delegated to the endpoint)

    • checkIfMatch

      protected boolean checkIfMatch(HttpServletRequest request, HttpServletResponse response, WebResource resource) throws IOException
      Check if the if-match condition is satisfied.
      Parameters:
      request - The servlet request we are processing
      response - The servlet response we are creating
      resource - The resource
      Returns:
      true if the resource meets the specified condition, and false if the condition is not satisfied, in which case request processing is stopped
      Throws:
      IOException - an IO error occurred

    • checkIfModifiedSince

      protected boolean checkIfModifiedSince(HttpServletRequest request, HttpServletResponse response, WebResource resource)
      Check if the if-modified-since condition is satisfied.
      Parameters:
      request - The servlet request we are processing
      response - The servlet response we are creating
      resource - The resource
      Returns:
      true if the resource meets the specified condition, and false if the condition is not satisfied, in which case request processing is stopped

    • checkIfNoneMatch

      protected boolean checkIfNoneMatch(HttpServletRequest request, HttpServletResponse response, WebResource resource) throws IOException
      Check if the if-none-match condition is satisfied.
      Parameters:
      request - The servlet request we are processing
      response - The servlet response we are creating
      resource - The resource
      Returns:
      true if the resource meets the specified condition, and false if the condition is not satisfied, in which case request processing is stopped
      Throws:
      IOException - an IO error occurred

    • checkIfUnmodifiedSince

      protected boolean checkIfUnmodifiedSince(HttpServletRequest request, HttpServletResponse response, WebResource resource) throws IOException
      Check if the if-unmodified-since condition is satisfied.
      Parameters:
      request - The servlet request we are processing
      response - The servlet response we are creating
      resource - The resource
      Returns:
      true if the resource meets the specified condition, and false if the condition is not satisfied, in which case request processing is stopped
      Throws:
      IOException - an IO error occurred

    • generateETag

      protected String generateETag(WebResource resource)
      Provides the entity tag (the ETag header) for the given resource. Intended to be over-ridden by custom DefaultServlet implementations that wish to use an alternative format for the entity tag.
      Parameters:
      resource - The resource for which an entity tag is required.
      Returns:
      The result of calling WebResource.getETag() on the given resource

    • copy

      @Deprecated protected void copy(WebResource resource, InputStream is, ServletOutputStream ostream) throws IOException
      Deprecated.
      Unused. This will be removed in Tomcat 9. Use copy(InputStream, ServletOutputStream)
      Copy the contents of the specified input stream to the specified output stream, and ensure that both streams are closed before returning (even in the face of an exception).
      Parameters:
      resource - The source resource
      is - The input stream to read the source resource from
      ostream - The output stream to write to
      Throws:
      IOException - if an input/output error occurs

    • copy

      protected void copy(InputStream is, ServletOutputStream ostream) throws IOException
      Copy the contents of the specified input stream to the specified output stream, and ensure that both streams are closed before returning (even in the face of an exception).
      Parameters:
      is - The input stream to read the source resource from
      ostream - The output stream to write to
      Throws:
      IOException - if an input/output error occurs

    • copy

      @Deprecated protected void copy(WebResource resource, InputStream is, PrintWriter writer, String encoding) throws IOException
      Deprecated.
      Unused. This will be removed in Tomcat 9. Use copy(InputStream, PrintWriter, String)
      Copy the contents of the specified input stream to the specified output stream, and ensure that both streams are closed before returning (even in the face of an exception).
      Parameters:
      resource - The source resource
      is - The input stream to read the source resource from
      writer - The writer to write to
      encoding - The encoding to use when reading the source input stream
      Throws:
      IOException - if an input/output error occurs

    • copy

      protected void copy(InputStream is, PrintWriter writer, String encoding) throws IOException
      Copy the contents of the specified input stream to the specified output stream, and ensure that both streams are closed before returning (even in the face of an exception).
      Parameters:
      is - The input stream to read the source resource from
      writer - The writer to write to
      encoding - The encoding to use when reading the source input stream
      Throws:
      IOException - if an input/output error occurs

    • copy

      protected void copy(WebResource resource, ServletOutputStream ostream, DefaultServlet.Range range) throws IOException
      Copy the contents of the specified input stream to the specified output stream, and ensure that both streams are closed before returning (even in the face of an exception).
      Parameters:
      resource - The source resource
      ostream - The output stream to write to
      range - Range the client wanted to retrieve
      Throws:
      IOException - if an input/output error occurs

    • copy

      protected void copy(WebResource resource, ServletOutputStream ostream, Iterator<DefaultServlet.Range> ranges, String contentType) throws IOException
      Copy the contents of the specified input stream to the specified output stream, and ensure that both streams are closed before returning (even in the face of an exception).
      Parameters:
      resource - The source resource
      ostream - The output stream to write to
      ranges - Enumeration of the ranges the client wanted to retrieve
      contentType - Content type of the resource
      Throws:
      IOException - if an input/output error occurs

    • copyRange

      protected IOException copyRange(InputStream istream, ServletOutputStream ostream)
      Copy the contents of the specified input stream to the specified output stream, and ensure that both streams are closed before returning (even in the face of an exception).
      Parameters:
      istream - The input stream to read from
      ostream - The output stream to write to
      Returns:
      Exception which occurred during processing

    • copyRange

      protected IOException copyRange(Reader reader, PrintWriter writer)
      Copy the contents of the specified input stream to the specified output stream, and ensure that both streams are closed before returning (even in the face of an exception).
      Parameters:
      reader - The reader to read from
      writer - The writer to write to
      Returns:
      Exception which occurred during processing

    • copyRange

      protected IOException copyRange(InputStream istream, ServletOutputStream ostream, long start, long end)
      Copy the contents of the specified input stream to the specified output stream, and ensure that both streams are closed before returning (even in the face of an exception).
      Parameters:
      istream - The input stream to read from
      ostream - The output stream to write to
      start - Start of the range which will be copied
      end - End of the range which will be copied
      Returns:
      Exception which occurred during processing