opendap.dap

Class DConnect2

java.lang.Object

opendap.dap.DConnect2

public class DConnect2
extends Object

Rewritten 1/15/07 jcaron to use HttpCLient library instead of jdk UrlConnection class. Need more robust redirect and authentication.

This class provides support for common DODS client-side operations such as dereferencing a OPeNDAP URL, communicating network activity status to the user and reading local OPeNDAP objects.

Unlike its C++ counterpart, this class does not store instances of the DAS, DDS, etc. objects. Rather, the methods getDAS, etc. return instances of those objects.

Author:

jehamby

Constructor Summary

Constructors

Constructor and Description
DConnect2(InputStream stream)
DConnect2(String urlString) Creates an instance bound to url which accepts compressed documents.
DConnect2(String urlString, boolean acceptCompress) Creates an instance bound to url.

Method Summary

Methods

Modifier and Type	Method and Description
static String	captureDataDDS(InputStream is)
static String	captureStream(InputStream is)
String	CE() Returns the constraint expression supplied with the URL given to the constructor.
void	closeSession()
DAS	getDAS() Returns the DAS object from the dataset referenced by this object's URL.
DataDDS	getData(StatusUI statusUI) Return the data object with no local constraint expression.
DataDDS	getData(String CE)
DataDDS	getData(String CE, StatusUI statusUI) Returns the `Data object' from the dataset referenced by this object's URL given the constraint expression CE.
DataDDS	getData(String CE, StatusUI statusUI, BaseTypeFactory btf) Returns the `Data object' from the dataset referenced by this object's URL given the constraint expression CE.
DataDDS	getDataDDX() Returns the DataDDS object from the dataset referenced by this object's URL.
DataDDS	getDataDDX(String CE) Returns the DataDDS object from the dataset referenced by this object's URL.
DataDDS	getDataDDX(String CE, BaseTypeFactory btf) Returns the DataDDS object from the dataset referenced by this object's URL.
DDS	getDDS() Returns the DDS object from the dataset referenced by this object's URL.
DDS	getDDS(String CE) Returns the DDS object from the dataset referenced by this object's URL.
DDS	getDDX() Returns the DDS object from the dataset referenced by this object's URL.
DDS	getDDX(String CE) Returns the DDS object from the dataset referenced by this object's URL.
String	getLastExtendedHeader()
String	getLastModifiedHeader()
String	getLastModifiedInvalidHeader()
ServerVersion	getServerVersion() Returns the ServerVersion of the last connection.
boolean	isLocal()
static void	main(String[] args)
static void	setAllowSessions(boolean b)
void	setServerVersion(int major, int minor)
String	URL() Returns the URL supplied to the constructor.

Methods inherited from class java.lang.Object

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

Constructor Detail

DConnect2

public DConnect2(String urlString)
          throws FileNotFoundException

Creates an instance bound to url which accepts compressed documents.

Parameters:

urlString - connect to this URL.

Throws:

FileNotFoundException - thrown if urlString is not a valid URL, or a filename which exists on the system.

DConnect2

public DConnect2(String urlString,
         boolean acceptCompress)
          throws FileNotFoundException

Creates an instance bound to url. If acceptDeflate is true then HTTP Request headers will indicate to servers that this client can accept compressed documents.

Parameters:

urlString - Connect to this URL.

acceptCompress - true if this client will accept compressed responses

Throws:

FileNotFoundException - thrown if urlString is not a valid URL, or a filename which exists on the system.

DConnect2

public DConnect2(InputStream stream)
          throws DAP2Exception

Throws:

DAP2Exception

Method Detail

setAllowSessions

public static void setAllowSessions(boolean b)

setServerVersion

public void setServerVersion(int major,
                    int minor)

isLocal

public boolean isLocal()

CE

public final String CE()

Returns the constraint expression supplied with the URL given to the constructor. If no CE was given this returns an empty String.

Note that the CE supplied to one of this object's constructors is "sticky"; it will be used with every data request made with this object. The CE passed to getData, however, is not sticky; it is used only for that specific request. This method returns the sticky CE.

Returns:

the constraint expression associated with this connection.

URL

public final String URL()

Returns the URL supplied to the constructor. If the URL contained a constraint expression that is not returned.

Returns:

the URL of this connection.

closeSession

public void closeSession()

captureStream

public static String captureStream(InputStream is)
                            throws IOException

Throws:

IOException

captureDataDDS

public static String captureDataDDS(InputStream is)
                             throws IOException

Throws:

IOException

getServerVersion

public final ServerVersion getServerVersion()

Returns the ServerVersion of the last connection.

Returns:

the ServerVersion of the last connection.

getLastModifiedHeader

public String getLastModifiedHeader()

Returns:

value of Last-Modified Header from last connection, may be null

getLastModifiedInvalidHeader

public String getLastModifiedInvalidHeader()

Returns:

value of X-Last-Modified-Invalid Header from last connection, may be null

getLastExtendedHeader

public String getLastExtendedHeader()

Returns:

value of Last-Extended Header from last connection, may be null

getDAS

public DAS getDAS()
           throws IOException,
                  DAP2Exception

Returns the DAS object from the dataset referenced by this object's URL. The DAS object is referred to by appending `.das' to the end of a DODS URL.

Returns:

the DAS associated with the referenced dataset.

Throws:

MalformedURLException - if the URL given to the constructor has an error

IOException - if an error connecting to the remote server

DASException - on an error constructing the DAS

DAP2Exception - if an error returned by the remote server

getDDS

public DDS getDDS()
           throws IOException,
                  ParseException,
                  DAP2Exception

Returns the DDS object from the dataset referenced by this object's URL. The DDS object is referred to by appending `.dds' to the end of a OPeNDAP URL.

Returns:

the DDS associated with the referenced dataset.

Throws:

MalformedURLException - if the URL given to the constructor has an error

IOException - if an error connecting to the remote server

ParseException - if the DDS parser returned an error

DDSException - on an error constructing the DDS

DAP2Exception - if an error returned by the remote server

getDDS

public DDS getDDS(String CE)
           throws IOException,
                  ParseException,
                  DAP2Exception

Returns the DDS object from the dataset referenced by this object's URL. The DDS object is referred to by appending `.dds' to the end of a OPeNDAP URL.

Parameters:

CE - The constraint expression to be applied to this request by the server. This is combined with any CE given in the constructor.

Returns:

the DDS associated with the referenced dataset.

Throws:

MalformedURLException - if the URL given to the constructor has an error

IOException - if an error connecting to the remote server

ParseException - if the DDS parser returned an error

DDSException - on an error constructing the DDS

DAP2Exception - if an error returned by the remote server

getDDX

public DDS getDDX()
           throws IOException,
                  ParseException,
                  DAP2Exception

Returns the DDS object from the dataset referenced by this object's URL. The DDS object is referred to by appending `.ddx' to the end of a OPeNDAP URL. The server should send back a DDX (A DDS in XML format) which will get parsed here (locally) and a new DDS instantiated using the DDSXMLParser.

Returns:

the DDS associated with the referenced dataset.

Throws:

MalformedURLException - if the URL given to the constructor has an error

IOException - if an error connecting to the remote server

ParseException - if the DDS parser returned an error

DDSException - on an error constructing the DDS

DAP2Exception - if an error returned by the remote server

getDDX

public DDS getDDX(String CE)
           throws IOException,
                  ParseException,
                  DDSException,
                  DAP2Exception

Returns the DDS object from the dataset referenced by this object's URL. The DDS object is referred to by appending `.ddx' to the end of a OPeNDAP URL. The server should send back a DDX (A DDS in XML format) which will get parsed here (locally) and a new DDS instantiated using the DDSXMLParser.

Parameters:

CE - The constraint expression to be applied to this request by the server. This is combined with any CE given in the constructor.

Returns:

the DDS associated with the referenced dataset.

Throws:

MalformedURLException - if the URL given to the constructor has an error

IOException - if an error connecting to the remote server

ParseException - if the DDS parser returned an error

DDSException - on an error constructing the DDS

DAP2Exception - if an error returned by the remote server

getDataDDX

public DataDDS getDataDDX()
                   throws MalformedURLException,
                          IOException,
                          ParseException,
                          DDSException,
                          DAP2Exception

Returns the DataDDS object from the dataset referenced by this object's URL. The DDS object is referred to by appending `.ddx' to the end of a OPeNDAP URL. The server should send back a DDX (A DDS in XML format) which will get parsed here (locally) and a new DDS instantiated using the DDSXMLParser.

Returns:

the DataDDS associated with the referenced dataset.

Throws:

MalformedURLException - if the URL given to the constructor has an error

IOException - if an error connecting to the remote server

ParseException - if the DDS parser returned an error

DDSException - on an error constructing the DDS

DAP2Exception - if an error returned by the remote server

getDataDDX

public DataDDS getDataDDX(String CE)
                   throws MalformedURLException,
                          IOException,
                          ParseException,
                          DDSException,
                          DAP2Exception

Returns the DataDDS object from the dataset referenced by this object's URL. The DDS object is referred to by appending `.ddx' to the end of a OPeNDAP URL. The server should send back a DDX (A DDS in XML format) which will get parsed here (locally) and a new DDS instantiated using the DDSXMLParser.

Parameters:

CE - The constraint expression to use for this request.

Returns:

the DataDDS associated with the referenced dataset.

Throws:

MalformedURLException - if the URL given to the constructor has an error

IOException - if an error connecting to the remote server

ParseException - if the DDS parser returned an error

DDSException - on an error constructing the DDS

DAP2Exception - if an error returned by the remote server

getDataDDX

public DataDDS getDataDDX(String CE,
                 BaseTypeFactory btf)
                   throws MalformedURLException,
                          IOException,
                          ParseException,
                          DDSException,
                          DAP2Exception

Returns the DataDDS object from the dataset referenced by this object's URL. The DDS object is referred to by appending `.ddx' to the end of a OPeNDAP URL. The server should send back a DDX (A DDS in XML format) which will get parsed here (locally) and a new DDS instantiated using the DDSXMLParser.

Parameters:

CE - The constraint expression to use for this request.

btf - The BaseTypeFactory to build the member variables in the DDS with.

Returns:

the DataDDS associated with the referenced dataset.

Throws:

MalformedURLException - if the URL given to the constructor has an error

IOException - if an error connecting to the remote server

ParseException - if the DDS parser returned an error

DDSException - on an error constructing the DDS

DAP2Exception - if an error returned by the remote server

See Also:

BaseTypeFactory

getData

public DataDDS getData(String CE,
              StatusUI statusUI,
              BaseTypeFactory btf)
                throws MalformedURLException,
                       IOException,
                       ParseException,
                       DDSException,
                       DAP2Exception

Returns the `Data object' from the dataset referenced by this object's URL given the constraint expression CE. Note that the Data object is really just a DDS object with data bound to the variables. The DDS will probably contain fewer variables (and those might have different types) than in the DDS returned by getDDS() because that method returns the entire DDS (but without any data) while this method returns only those variables listed in the projection part of the constraint expression.

Note that if CE is an empty String then the entire dataset will be returned, unless a "sticky" CE has been specified in the constructor.

Parameters:

CE - The constraint expression to be applied to this request by the server. This is combined with any CE given in the constructor.

statusUI - the StatusUI object to use for GUI updates and user cancellation notification (may be null).

btf - The BaseTypeFactory to build the member variables in the DDS with.

Returns:

The DataDDS object that results from applying the given CE, combined with this object's sticky CE, on the referenced dataset.

Throws:

MalformedURLException - if the URL given to the constructor has an error

IOException - if any error connecting to the remote server

ParseException - if the DDS parser returned an error

DDSException - on an error constructing the DDS

DAP2Exception - if any error returned by the remote server

getData

public DataDDS getData(String CE)
                throws IOException,
                       ParseException,
                       DAP2Exception

Throws:

IOException

ParseException

DAP2Exception

getData

public DataDDS getData(String CE,
              StatusUI statusUI)
                throws MalformedURLException,
                       IOException,
                       ParseException,
                       DDSException,
                       DAP2Exception

Returns the `Data object' from the dataset referenced by this object's URL given the constraint expression CE. Note that the Data object is really just a DDS object with data bound to the variables. The DDS will probably contain fewer variables (and those might have different types) than in the DDS returned by getDDS() because that method returns the entire DDS (but without any data) while this method returns only those variables listed in the projection part of the constraint expression.

Note that if CE is an empty String then the entire dataset will be returned, unless a "sticky" CE has been specified in the constructor.

Parameters:

CE - The constraint expression to be applied to this request by the server. This is combined with any CE given in the constructor.

statusUI - the StatusUI object to use for GUI updates and user cancellation notification (may be null).

Returns:

The DataDDS object that results from applying the given CE, combined with this object's sticky CE, on the referenced dataset.

Throws:

MalformedURLException - if the URL given to the constructor has an error

IOException - if any error connecting to the remote server

ParseException - if the DDS parser returned an error

DDSException - on an error constructing the DDS

DAP2Exception - if any error returned by the remote server

getData

public final DataDDS getData(StatusUI statusUI)
                      throws MalformedURLException,
                             IOException,
                             ParseException,
                             DDSException,
                             DAP2Exception

Return the data object with no local constraint expression. Same as getData("", statusUI).

Parameters:

statusUI - the StatusUI object to use for GUI updates and user cancellation notification (may be null).

Returns:

The DataDDS object that results from applying this object's sticky CE, if any, on the referenced dataset.

Throws:

MalformedURLException - if the URL given to the constructor has an error

IOException - if any error connecting to the remote server

ParseException - if the DDS parser returned an error

DDSException - on an error constructing the DDS

DAP2Exception - if any error returned by the remote server

main

public static void main(String[] args)

Parameters:

args - command line arguments