com.goebl.david

Class Response<T>

java.lang.Object

com.goebl.david.Response<T>

public class Response<T>
extends Object

Holds data about the response message returning from HTTP request.

Author:

hgoebl

Method Summary

Modifier and Type	Method and Description
void	ensureSuccess() A shortcut to check for successful status codes and throw exception in case of non-2xx status codes.
T	getBody() Returns the payload of the response converted to the given type.
HttpURLConnection	getConnection() Get the "real" connection, typically to call some getters which are not provided by this Response object.
String	getContentType() Returns the MIME-type of the response body.
long	getDate() Returns the date when the request was created (server-time).
Object	getErrorBody() Get the body which was returned in case of error (HTTP-Code >= 400).
long	getExpiration() Returns the value of the expires header field.
String	getHeaderField(String name) Returns the value of the named header field.
long	getHeaderFieldDate(String field, long defaultValue) Returns the value of the named field parsed as date (Millis since 1970).
int	getHeaderFieldInt(String field, int defaultValue) Returns the value of the named field parsed as a number.
long	getLastModified() Returns the value of the last-modified header field.
Request	getRequest() Access to the Request object (which will not be very useful in most cases).
String	getResponseMessage() Returns the text explaining the status code.
int	getStatusCode() See HttpURLConnection.responseCode
String	getStatusLine() The first line returned by the web-server, like "HTTP/1.1 200 OK".
boolean	isSuccess() Was the request successful (returning a 2xx status code)?

Methods inherited from class java.lang.Object

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

Method Detail

getRequest

public Request getRequest()

Access to the Request object (which will not be very useful in most cases).

Returns:

the request object which was responsible for creating this response.

getBody

public T getBody()

Returns the payload of the response converted to the given type.

Returns:

the converted payload (can be null).

getErrorBody

public Object getErrorBody()

Get the body which was returned in case of error (HTTP-Code >= 400).
The type of the error body depends on following factors:

• Content-Type header (overrules the expected return type of the response)
• The expected type (see asXyz()). We try to coerce the error body to this type. In case of REST services, where often a JSONObject is the normal response body, the error body will be converted to JSONObject if possible. JSONArray is not expected to be the error body.

If converting the error body is not successful, String and byte[] is used as a fallback. You have to check the type with instanceof or try/catch the cast.

Returns:

the error body converted to an object (see above) or null if there is no body or no error.

getStatusCode

public int getStatusCode()

See HttpURLConnection.responseCode

Returns:

An int representing the three digit HTTP Status-Code.

getStatusLine

public String getStatusLine()

The first line returned by the web-server, like "HTTP/1.1 200 OK".

Returns:

first header

isSuccess

public boolean isSuccess()

Was the request successful (returning a 2xx status code)?

Returns:

true when status code is between 200 and 299, else false

getResponseMessage

public String getResponseMessage()

Returns the text explaining the status code.

Returns:

e.g. "Moved Permanently", "Created", ...

getContentType

public String getContentType()

Returns the MIME-type of the response body.
See URLConnection.getContentType()

Returns:

e.g. "application/json", "text/plain", ...

getDate

public long getDate()

Returns the date when the request was created (server-time).
See URLConnection.getDate()

Returns:

the parsed "Date" header as millis or 0 if this header was not set.

getExpiration

public long getExpiration()

Returns the value of the expires header field.
See URLConnection.getExpiration()

Returns:

the expiration date of the resource, or 0 if not known.

getLastModified

public long getLastModified()

Returns the value of the last-modified header field.
See URLConnection.getLastModified()

Returns:

the date the resource was last modified, or 0 if not known.

getHeaderField

public String getHeaderField(String name)

Returns the value of the named header field.
See URLConnection.getHeaderField()

Parameters:

name - name of the header field

Returns:

the value of the named header field, or null

getHeaderFieldDate

public long getHeaderFieldDate(String field,
                               long defaultValue)

Returns the value of the named field parsed as date (Millis since 1970).
See URLConnection.getHeaderFieldDate()

Parameters:

field - name of the header field

defaultValue - the default value if the field is not present or malformed

Returns:

the value of the named header field, or the given default value

getHeaderFieldInt

public int getHeaderFieldInt(String field,
                             int defaultValue)

Returns the value of the named field parsed as a number.
See URLConnection.getHeaderFieldInt()

Parameters:

field - name of the header field

defaultValue - the default value if the field is not present or malformed

Returns:

the value of the named header field, or the given default value

getConnection

public HttpURLConnection getConnection()

Get the "real" connection, typically to call some getters which are not provided by this Response object.

Returns:

the connection object (many methods throw IllegalStateException depending on the internal state).

ensureSuccess

public void ensureSuccess()

A shortcut to check for successful status codes and throw exception in case of non-2xx status codes.
In many cases you will call Request.ensureSuccess() instead of this method. But there might be cases where you want to inspect the response-object first (check header values) and then have a short exit where the response-code is not suitable for further normal processing.