RestTemplate getForObject() vs getForEntity()

Asked on November 13, 2020
What is difference between Spring RestTemplate.getForObject() and RestTemplate.getForEntity() ?

Replied on November 14, 2020
RestTemplate.getForObject()
Find the getForObject method declarations.
1.
T getForObject(URI url, Class<T> responseType)
2.
T getForObject(String url, Class<T> responseType, Object... uriVariables)
3.
T getForObject(String url, Class<T> responseType, Map<String,?> uriVariables)
Example:
Client code
String url = "http://localhost:8080/employee/{profile}/{tech}";
Map<String, String> map = new HashMap<>();
map.put("profile", "Developer");
map.put("tech", "Java");
Employee[] emps = restTemplate.getForObject(url, Employee[].class, map);
In the above code the URI variables has been passed as Map. If we want to use object varargs in the above code, we can do it as following.
String profile = "Developer";
String tech = "Java";
Employee[] emps = restTemplate.getForObject(url, Employee[].class, profile, tech);
Now find the Server code.
@GetMapping("employee/{profile}/{tech}")
public ResponseEntity<List<Employee>> getEmployeesByProfileNTech(@PathVariable("profile") String profile,
@PathVariable("tech") String technology) {
------
}
RestTemplate.getForEntity()
The getForEntity method retrieves resources from the given URI or URL templates. It returns response as ResponseEntity using which we can get response status code, response body etc. To fetch data on the basis of some key properties, we can send them as path variables. We need to use URI template and pass a Map or Object varargs to getForEntity method to expand it on URI template.
1.
ResponseEntity<T> getForEntity(URI url, Class<T> responseType)
2.
ResponseEntity<T> getForEntity(String url, Class<T> responseType, Object... uriVariables)
3.
ResponseEntity<T> getForEntity(String url, Class<T> responseType, Map<String,?> uriVariables)
Example:
Client code
String url = "http://localhost:8080/employee/{profile}/{tech}";
Map<String, String> map = new HashMap<>();
map.put("profile", "Developer");
map.put("tech", "Java");
ResponseEntity<Employee[]> responseEntity = restTemplate.getForEntity(url, Employee[].class, map);
In the above code the URI variables has been passed as Map. If we want to use object varargs in the above code, we can do it as following.
String profile = "Developer";
String tech = "Java";
ResponseEntity<Employee[]> responseEntity = restTemplate.getForEntity(url, Employee[].class, profile, tech);
Now find the Server code.
@GetMapping("employee/{profile}/{tech}")
public ResponseEntity<List<Employee>> getEmployeesByProfileNTech(@PathVariable("profile") String profile,
@PathVariable("tech") String technology) {
------
}