Interface: javax.servlet.ServletRequest

  • public interface ServletRequest
Defines an object to provide client request information to a servlet. The servlet container creates a ServletRequest object and passes it as an argument to the servlet's service method.

A ServletRequest object provides data including parameter name and values, attributes, and an input stream. Interfaces that extend ServletRequest can provide additional protocol-specific data (for example, HTTP data is provided by javax.servlet.http.HttpServletRequest.

Authors:
@author Various
See:
@see javax.servlet.http.HttpServletRequest

Methods

  • getAttributetop

    public Object getAttribute(String name)
    Returns the value of the named attribute as an Object, or null if no attribute of the given name exists.

    Attributes can be set two ways. The servlet container may set attributes to make available custom information about a request. For example, for requests made using HTTPS, the attribute javax.servlet.request.X509Certificate can be used to retrieve information on the certificate of the client. Attributes can also be set programatically using javax.servlet.ServletRequest.setAttribute(java.lang.String, java.lang.Object). This allows information to be embedded into a request before a javax.servlet.RequestDispatcher call.

    Attribute names should follow the same conventions as package names. This specification reserves names matching java.*, javax.*, and sun.*.

    Parameters:
    @param name a String specifying the name of the attribute
    Return:
    @return an Object containing the value of the attribute, or null if the attribute does not exist
    Google Code Search
    Stack Overflow
  • getAttributeNamestop

    public Enumeration getAttributeNames()
    Returns an Enumeration containing the names of the attributes available to this request. This method returns an empty Enumeration if the request has no attributes available to it.
    Return:
    @return an Enumeration of strings containing the names of the request's attributes
    Google Code Search
    Stack Overflow
  • getCharacterEncodingtop

    public String getCharacterEncoding()
    Returns the name of the character encoding used in the body of this request. This method returns null if the request does not specify a character encoding
    Return:
    @return a String containing the name of the character encoding, or null if the request does not specify a character encoding
    Google Code Search
    Stack Overflow
  • getContentLengthtop

    public int getContentLength()
    Returns the length, in bytes, of the request body and made available by the input stream, or -1 if the length is not known. For HTTP servlets, same as the value of the CGI variable CONTENT_LENGTH.
    Return:
    @return an integer containing the length of the request body or -1 if the length is not known
    Google Code Search
    Stack Overflow
  • getContentTypetop

    public String getContentType()
    Returns the MIME type of the body of the request, or null if the type is not known. For HTTP servlets, same as the value of the CGI variable CONTENT_TYPE.
    Return:
    @return a String containing the name of the MIME type of the request, or null if the type is not known
    Google Code Search
    Stack Overflow
  • getInputStreamtop

    public ServletInputStream getInputStream() throws IOException
    Retrieves the body of the request as binary data using a javax.servlet.ServletInputStream. Either this method or javax.servlet.ServletRequest.getReader() may be called to read the body, not both.
    Return:
    @return a javax.servlet.ServletInputStream object containing the body of the request
    Exceptions:
    @exception IllegalStateException if the javax.servlet.ServletRequest.getReader() method has already been called for this request
    @exception java.io.IOException if an input or output exception occurred
    Google Code Search
    Stack Overflow
  • getLocalAddrtop

    public String getLocalAddr()
    Returns the Internet Protocol (IP) address of the interface on which the request was received.
    Return:
    @return a String containing the IP address on which the request was received.
    Since:
    @since 2.4
    Google Code Search
    Stack Overflow
  • getLocalNametop

    public String getLocalName()
    Returns the host name of the Internet Protocol (IP) interface on which the request was received.
    Return:
    @return a String containing the host name of the IP on which the request was received.
    Since:
    @since 2.4
    Google Code Search
    Stack Overflow
  • getLocalPorttop

    public int getLocalPort()
    Returns the Internet Protocol (IP) port number of the interface on which the request was received.
    Return:
    @return an integer specifying the port number
    Since:
    @since 2.4
    Google Code Search
    Stack Overflow
  • getLocaletop

    public Locale getLocale()
    Returns the preferred Locale that the client will accept content in, based on the Accept-Language header. If the client request doesn't provide an Accept-Language header, this method returns the default locale for the server.
    Return:
    @return the preferred Locale for the client
    Google Code Search
    Stack Overflow
  • getLocalestop

    public Enumeration getLocales()
    Returns an Enumeration of Locale objects indicating, in decreasing order starting with the preferred locale, the locales that are acceptable to the client based on the Accept-Language header. If the client request doesn't provide an Accept-Language header, this method returns an Enumeration containing one Locale, the default locale for the server.
    Return:
    @return an Enumeration of preferred Locale objects for the client
    Google Code Search
    Stack Overflow
  • getParametertop

    public String getParameter(String name)
    Returns the value of a request parameter as a String, or null if the parameter does not exist. Request parameters are extra information sent with the request. For HTTP servlets, parameters are contained in the query string or posted form data.

    You should only use this method when you are sure the parameter has only one value. If the parameter might have more than one value, use javax.servlet.ServletRequest.getParameterValues(java.lang.String).

    If you use this method with a multivalued parameter, the value returned is equal to the first value in the array returned by getParameterValues.

    If the parameter data was sent in the request body, such as occurs with an HTTP POST request, then reading the body directly via javax.servlet.ServletRequest.getInputStream() or javax.servlet.ServletRequest.getReader() can interfere with the execution of this method.

    Parameters:
    @param name a String specifying the name of the parameter
    Return:
    @return a String representing the single value of the parameter
    See:
    @see javax.servlet.ServletRequest.getParameterValues(java.lang.String)
    Google Code Search
    Stack Overflow
  • getParameterMaptop

    public Map getParameterMap()
    Returns a java.util.Map of the parameters of this request. Request parameters are extra information sent with the request. For HTTP servlets, parameters are contained in the query string or posted form data.
    Return:
    @return an immutable java.util.Map containing parameter names as keys and parameter values as map values. The keys in the parameter map are of type String. The values in the parameter map are of type String array.
    Google Code Search
    Stack Overflow
  • getParameterNamestop

    public Enumeration getParameterNames()
    Returns an Enumeration of String objects containing the names of the parameters contained in this request. If the request has no parameters, the method returns an empty Enumeration.
    Return:
    @return an Enumeration of String objects, each String containing the name of a request parameter; or an empty Enumeration if the request has no parameters
    Google Code Search
    Stack Overflow
  • getParameterValuestop

    public String[] getParameterValues(String name)
    Returns an array of String objects containing all of the values the given request parameter has, or null if the parameter does not exist.

    If the parameter has a single value, the array has a length of 1.

    Parameters:
    @param name a String containing the name of the parameter whose value is requested
    Return:
    @return an array of String objects containing the parameter's values
    See:
    @see javax.servlet.ServletRequest.getParameter(java.lang.String)
    Google Code Search
    Stack Overflow
  • getProtocoltop

    public String getProtocol()
    Returns the name and version of the protocol the request uses in the form protocol/majorVersion.minorVersion, for example, HTTP/1.1. For HTTP servlets, the value returned is the same as the value of the CGI variable SERVER_PROTOCOL.
    Return:
    @return a String containing the protocol name and version number
    Google Code Search
    Stack Overflow
  • getReadertop

    public BufferedReader getReader() throws IOException
    Retrieves the body of the request as character data using a BufferedReader. The reader translates the character data according to the character encoding used on the body. Either this method or javax.servlet.ServletRequest.getInputStream() may be called to read the body, not both.
    Return:
    @return a BufferedReader containing the body of the request
    Exceptions:
    @exception UnsupportedEncodingException if the character set encoding used is not supported and the text cannot be decoded
    @exception IllegalStateException if javax.servlet.ServletRequest.getInputStream() method has been called on this request
    @exception java.io.IOException if an input or output exception occurred
    See:
    @see javax.servlet.ServletRequest.getInputStream()
    Google Code Search
    Stack Overflow
  • getRealPathtop

    public String getRealPath(String path)
    Deprecated:
    @deprecated As of Version 2.1 of the Java Servlet API, use javax.servlet.ServletContext.getRealPath(java.lang.String) instead.
    Google Code Search
    Stack Overflow
  • getRemoteAddrtop

    public String getRemoteAddr()
    Returns the Internet Protocol (IP) address of the client or last proxy that sent the request. For HTTP servlets, same as the value of the CGI variable REMOTE_ADDR.
    Return:
    @return a String containing the IP address of the client that sent the request
    Google Code Search
    Stack Overflow
  • getRemoteHosttop

    public String getRemoteHost()
    Returns the fully qualified name of the client or the last proxy that sent the request. If the engine cannot or chooses not to resolve the hostname (to improve performance), this method returns the dotted-string form of the IP address. For HTTP servlets, same as the value of the CGI variable REMOTE_HOST.
    Return:
    @return a String containing the fully qualified name of the client
    Google Code Search
    Stack Overflow
  • getRemotePorttop

    public int getRemotePort()
    Returns the Internet Protocol (IP) source port of the client or last proxy that sent the request.
    Return:
    @return an integer specifying the port number
    Since:
    @since 2.4
    Google Code Search
    Stack Overflow
  • getRequestDispatchertop

    public RequestDispatcher getRequestDispatcher(String path)
    Returns a javax.servlet.RequestDispatcher object that acts as a wrapper for the resource located at the given path. A RequestDispatcher object can be used to forward a request to the resource or to include the resource in a response. The resource can be dynamic or static.

    The pathname specified may be relative, although it cannot extend outside the current servlet context. If the path begins with a "/" it is interpreted as relative to the current context root. This method returns null if the servlet container cannot return a RequestDispatcher.

    The difference between this method and javax.servlet.ServletContext.getRequestDispatcher(java.lang.String) is that this method can take a relative path.

    Parameters:
    @param path a String specifying the pathname to the resource. If it is relative, it must be relative against the current servlet.
    Return:
    @return a RequestDispatcher object that acts as a wrapper for the resource at the specified path, or null if the servlet container cannot return a RequestDispatcher
    See:
    @see javax.servlet.RequestDispatcher
    @see javax.servlet.ServletContext.getRequestDispatcher(java.lang.String)
    Google Code Search
    Stack Overflow
  • getSchemetop

    public String getScheme()
    Returns the name of the scheme used to make this request, for example, http, https, or ftp. Different schemes have different rules for constructing URLs, as noted in RFC 1738.
    Return:
    @return a String containing the name of the scheme used to make this request
    Google Code Search
    Stack Overflow
  • getServerNametop

    public String getServerName()
    Returns the host name of the server to which the request was sent. It is the value of the part before ":" in the Host header value, if any, or the resolved server name, or the server IP address.
    Return:
    @return a String containing the name of the server
    Google Code Search
    Stack Overflow
  • getServerPorttop

    public int getServerPort()
    Returns the port number to which the request was sent. It is the value of the part after ":" in the Host header value, if any, or the server port where the client connection was accepted on.
    Return:
    @return an integer specifying the port number
    Google Code Search
    Stack Overflow
  • isSecuretop

    public boolean isSecure()
    Returns a boolean indicating whether this request was made using a secure channel, such as HTTPS.
    Return:
    @return a boolean indicating if the request was made using a secure channel
    Google Code Search
    Stack Overflow
  • removeAttributetop

    public void removeAttribute(String name)
    Removes an attribute from this request. This method is not generally needed as attributes only persist as long as the request is being handled.

    Attribute names should follow the same conventions as package names. Names beginning with java.*, javax.*, and com.sun.*, are reserved for use by Sun Microsystems.

    Parameters:
    @param name a String specifying the name of the attribute to remove
    Google Code Search
    Stack Overflow
  • setAttributetop

    public void setAttribute(String name, Object o)
    Stores an attribute in this request. Attributes are reset between requests. This method is most often used in conjunction with javax.servlet.RequestDispatcher.

    Attribute names should follow the same conventions as package names. Names beginning with java.*, javax.*, and com.sun.*, are reserved for use by Sun Microsystems.
    If the object passed in is null, the effect is the same as calling javax.servlet.ServletRequest.removeAttribute(java.lang.String).
    It is warned that when the request is dispatched from the servlet resides in a different web application by RequestDispatcher, the object set by this method may not be correctly retrieved in the caller servlet.

    Parameters:
    @param name a String specifying the name of the attribute
    @param o the Object to be stored
    Google Code Search
    Stack Overflow
  • setCharacterEncodingtop

    public void setCharacterEncoding(String env) throws UnsupportedEncodingException
    Overrides the name of the character encoding used in the body of this request. This method must be called prior to reading request parameters or reading input using getReader(). Otherwise, it has no effect.
    Parameters:
    @param env String containing the name of the character encoding.
    Exceptions:
    @throws java.io.UnsupportedEncodingException if this ServletRequest is still in a state where a character encoding may be set, but the specified encoding is invalid
    Google Code Search
    Stack Overflow