# Java Core APIs

## Introduction

The Java Core APIs provide the client-side Java interfaces to set up connection with the server, package or unpackage requests and responses in XML format, query any API on the server, determine the queried result, and so on.

The Java Core APIs provides the following information:

- Java classes

- NaServer—This class provides the methods to set up server connection and session parameters, send any API to the server, parse the queried results, and so on.

- NaElement—This class encapsulates the input output (I/O) elements. An NaElement encapsulates one level of an I/O element. You can nest these I/O elements arbitrarily. They have names, corresponding to the XML tags, attributes (only used for results), values (always strings), and children, corresponding to the nested tagged items. The methods of this class are used to package the requests and responses, create new elements, change the contents of the elements, and so on.

- NaProxyServer—This class provides methods used to connect to proxy servers and to invoke the API.

- Interface

- NaErrno—This interface provides the error code constants for Data ONTAP APIs.

- DfmErrno—This interface provides the error code contants for DataFabric Manager APIs.

- Exceptions

- NaAPIFailedException—This class encapsulates API invocation failures. The methods of this class are used to extract error codes and error strings upon an API failure.

- NaAuthenticationException—This class encapsulates the exception that arises due to wrong authentication credentials.

- NaException—This is a parent class for all the exceptions that arise due to problems in the API invocation.

- NaProtocolException—This class encapsulates the exception that arises due to a protocol problem. This means that the server responded with something that is not identifiable. (In such cases, resending the request does not solve the problem.)

- NaProxyFailedException—This class encapsulates the proxy API invocation failures, which means that the proxy server received the proxy API request, but failed to forward the request to the target host.

- Errors

- NaError—This class is returned when there is a serious error in the library.

## Contents of this section

This section provides API information for the Java Core APIs. It includes the following classes, interfaces, exceptions, and errors:

- ARCFour

- Base16

- HTTPClient

- HTTPException

- HTTPMessage

- HTTPRequest

- HTTPResponse

- NaAPIFailedException

- NaAuthenticationException

- NaElement

- NaErrno

- NaError

- NaException

- NaProtocolException

- NaProxyFailedException

- NaProxyServer

- NaServer

Related Topic

- Library Information