RestClient (Ibello API 1.21.1 API)

```
public interface RestClient
```
This interface describes a REST client which sends a single request and receives a response.
A new instance of this interface can be configured with it's fluent methods. These methods return the same RestClient instance so the configuration can be performed with method call chain. At the end of this chain the sendAndReceive(Class) method should be called which executes the call and returns with the response.

The client instance has some default configuration.
- Default HTTP method is GET. This can be changed with the method(HttpMethod) method.
- Default request charset is UTF-8. This can be changed with charset(Charset) method.
- Default request MIME type is "application/json". This can be changed with mimeType(String) method.
- By default the "Accept" header is added to the request with "application/json" value. This can be changed with the accept(String) method.
Example REST API call:
```
 MyRequest data = ...;
 HttpResponse<MyResponse> response = restClient()
     .url("http://myservice.xy/service")
     .body(data)
     .basicAuthorization("user", "pwd")
     .sendAndReceive(MyResponse.class);
 
```
Author:

Kornél Simon

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method and Description
`RestClient`	`accept(String mimeType)` Sets the "Accept" header of the REST call.
`RestClient`	`authorization(String authorization)` Sets the "Authorization" header of the REST call.
`RestClient`	`basicAuthorization(String username, String password)` Sets the "Authorization" header of the REST call.
`RestClient`	`bearerAuthorization(String token)` Sets the "Authorization" header of the REST call.
`<T> RestClient`	`body(T object)` Sets the body of the REST call.
`RestClient`	`charset(Charset charset)` Sets the charset of the REST call's content.
`RestClient`	`charset(String charsetName)` Sets the charset of the REST call's content.
`RestClient`	`header(String name, String value)` Adds a HTTP header to the REST call.
`RestClient`	`method(HttpMethod method)` Sets the HTTP method of the REST call.
`RestClient`	`mimeType(String mimeType)` Sets the MIME type of the REST call's content.
`<T> HttpResponse<T>`	`sendAndReceive(Class<T> responseType)` Executes the REST call: sends the request and receives the response.
`<T> HttpResponse<List<T>>`	`sendAndReceiveList(Class<T> itemType)` Executes the REST call: sends the request and receives the response.
`RestClient`	`url(String url)` Sets the URL of the REST call.
`RestClient`	`url(URL url)` Sets the URL of the HTTP request.
`RestClient`	`withoutCertificateValidation()` Turns off SSL certificate validation.

- Method Detail
  - url
```
RestClient url(String url)
```
    Sets the URL of the REST call. The argument can be:
    - a full absolute URL with protocol and hostname, eg. http://localhost:8080/page,
    - a relative URL without host, eg. /page or service?param=x.
    If the URL is absolute, then it will be used by the REST client.
    
    If the URL is relative, then it will be appended to the value of the ibello.url.base configuration property, and the result URL will be used.
    Parameters:
    
    url - relative or absolute URL
    
    Returns:
    
    this RestClient instance
    
    Throws:
    
    NullPointerException - when the argument is null
  - url
```
RestClient url(URL url)
```
    Sets the URL of the HTTP request.
    
    Parameters:
    
    url - the URL
    
    Returns:
    
    this RestClient instance
    
    Throws:
    
    NullPointerException - when the argument is null
  - method
```
RestClient method(HttpMethod method)
```
    Sets the HTTP method of the REST call.
    
    Parameters:
    
    method - the HTTP method
    
    Returns:
    
    this RestClient instance
  - mimeType
```
RestClient mimeType(String mimeType)
```
    Sets the MIME type of the REST call's content.
    
    Parameters:
    
    mimeType - a valid MIME type
    
    Returns:
    
    this RestClient instance
  - charset
```
RestClient charset(Charset charset)
```
    Sets the charset of the REST call's content.
    
    Parameters:
    
    charset - a java Charset instance
    
    Returns:
    
    this RestClient instance
  - charset
```
RestClient charset(String charsetName)
```
    Sets the charset of the REST call's content.
    
    Parameters:
    
    charsetName - the name of the charset
    
    Returns:
    
    this RestClient instance
  - body
```
<T> RestClient body(T object)
```
    Sets the body of the REST call. The parameter can be:
    - a File instance, in this case a multipart attachment will be added to the body,
    - an InputStream instance, in this case the content of the stream will be the request body,
    - a String - it will be considered as a JSON value,
    - or anything else - which will be transformed to JSON.
    Type Parameters:
    
    T - the type of the body object
    
    Parameters:
    
    object - the object (or JSON string) to be sent
    
    Returns:
    
    this RestClient instance
  - header
```
RestClient header(String name,
                  String value)
```
    Adds a HTTP header to the REST call.
    
    Parameters:
    
    name - the name of the header
    
    value - the value of the header
    
    Returns:
    
    this RestClient instance
  - accept
```
RestClient accept(String mimeType)
```
    Sets the "Accept" header of the REST call.
    
    Parameters:
    
    mimeType - a valid MIME type
    
    Returns:
    
    this RestClient instance
  - authorization
```
RestClient authorization(String authorization)
```
    Sets the "Authorization" header of the REST call.
    
    Parameters:
    
    authorization - the value of the Authorization header
    
    Returns:
    
    this RestClient instance
  - basicAuthorization
```
RestClient basicAuthorization(String username,
                              String password)
```
    Sets the "Authorization" header of the REST call. It will be a "Basic" authorization value with the given username and password.
    
    Parameters:
    
    username - the authorization username
    
    password - the authorization password
    
    Returns:
    
    this RestClient instance
  - bearerAuthorization
```
RestClient bearerAuthorization(String token)
```
    Sets the "Authorization" header of the REST call. It will be a "Bearer" authorization value with the given token.
    
    Parameters:
    
    token - the authorization token
    
    Returns:
    
    this RestClient instance
  - withoutCertificateValidation
```
RestClient withoutCertificateValidation()
```
    Turns off SSL certificate validation. This is useful if the SSL certificate of the host is not valid from any reason but we need to communicate with it with HTTPS protocol.
    
    Returns:
    
    this RestClient instance
  - sendAndReceive
```
<T> HttpResponse<T> sendAndReceive(Class<T> responseType)
                            throws IOException,
                                   IllegalArgumentException
```
    Executes the REST call: sends the request and receives the response. It automatically transforms the response JSON to a java object. If the responseType argument is String.class, then the original JSON response will be returned in the result (without any transformation).
    
    Type Parameters:
    
    T - type of the response
    
    Parameters:
    
    responseType - class of the response
    
    Returns:
    
    the response as java object
    
    Throws:
    
    IOException - if the communication with the REST server failed
    
    IllegalArgumentException - if the response of the REST server was invalid
  - sendAndReceiveList
```
<T> HttpResponse<List<T>> sendAndReceiveList(Class<T> itemType)
                                      throws IOException,
                                             IllegalArgumentException
```
    Executes the REST call: sends the request and receives the response. It automatically transforms the response JSON to a java list.
    
    Type Parameters:
    
    T - type of the items in the response list
    
    Parameters:
    
    itemType - class of the items in the response list
    
    Returns:
    
    the response as java list
    
    Throws:
    
    IOException - if the communication with the REST server failed
    
    IllegalArgumentException - if the response of the REST server was invalid

Interface RestClient

Method Summary

Method Detail

url

url

method

mimeType

charset

charset

body

header

accept

authorization

basicAuthorization

bearerAuthorization

withoutCertificateValidation

sendAndReceive

sendAndReceiveList