java - Spring Boot - Global Custom Exception Handling Mechanism using RestControllerAdvice -

am using spring boot restful web services.

trying setup global custom exception handling mechanism relies on @restcontrolleradvice can handle exceptions known not known.

pom.xml

<parent>     <groupid>org.springframework.boot</groupid>     <artifactid>spring-boot-starter-parent</artifactid>     <version>1.5.4.release</version> </parent>  <properties>     <java.version>1.8</java.version> </properties>  <repositories>     <repository>         <id>spring-releases</id>         <url>https://repo.spring.io/libs-release</url>     </repository> </repositories>  <pluginrepositories>     <pluginrepository>         <id>spring-releases</id>         <url>https://repo.spring.io/libs-release</url>     </pluginrepository> </pluginrepositories>  <dependencies>     <!-- spring -->     <dependency>         <groupid>org.springframework.boot</groupid>         <artifactid>spring-boot-starter-web</artifactid>     </dependency>      <dependency>         <groupid>org.springframework.boot</groupid>         <artifactid>spring-boot-starter-test</artifactid>         <scope>test</scope>     </dependency> </dependencies> 

globalcontrollerexceptionhandler:

@restcontrolleradvice public class globalcontrollerexceptionhandler {      private static final logger log = logger.getlogger(globalcontrollerexceptionhandler.class);      @exceptionhandler(value = { constraintviolationexception.class })     @responsestatus(httpstatus.bad_request)     public apierrorresponse constraintviolationexception(constraintviolationexception ex) {         log.error(ex.getcause().tostring());         return new apierrorresponse(400, "bad request");     }      @exceptionhandler(value = { nohandlerfoundexception.class })     @responsestatus(httpstatus.not_found)     public apierrorresponse nohandlerfoundexception(exception ex) {         log.error(ex.getcause().tostring());         return new apierrorresponse(404, "resource not found");     }      @exceptionhandler(value = { exception.class })     @responsestatus(httpstatus.internal_server_error)     public apierrorresponse unknownexception(exception ex) {         log.error(ex.getcause().tostring());         return new apierrorresponse(500, "internal server error");     } } 

apierrorresponse:

public class apierrorresponse {      private int status;     private string message;      public apierrorresponse(int status, string message) {         this.status = status;         this.message = message;     }      public int getstatus() {         return status;     }      public string getmessage() {         return message;     }      @override     public string tostring() {         return new tostringbuilder(this).append(status)                                         .append(message)                                         .tostring();     } } 

the problem when use 3rd party library something, unknown exception might 404 returned 500!

e.g. using elasticsearch unknown index (deliberately see type of exception):

{   "timestamp": 1501236796640,   "status": 500,   "error": "internal server error",   "exception": "org.elasticsearch.client.responseexception",   "message": "post http://localhost:9200/fn3r4343/_search?pretty=true: http/1.1 404 not found"         {         "error": {             "root_cause": [                 {                     "type": "index_not_found_exception",                     "reason": "no such index",                     "resource.type": "index_or_alias",                     "resource.id": "fn3r4343",                     "index_uuid": "_na_",                     "index": "fn3r4343"                 }             ],             "type": "index_not_found_exception",             "reason": "nosuchindex",             "resource.type": "index_or_alias",             "resource.id": "fn3r4343",             "index_uuid": "_na_",             "index": "fn3r4343"         }         {  "root_cause" :              [                  {                     "type" :"index_not_found_exception",                     "reason" : no such index", "resource.type" : "index_or_alias",                     "resource.id" : "fn3r4343",                    "index_uuid" : "_na_",                    "index" : "fn3r4343"                 }             ],             [                       {                   "type" : "index_not_found_exception",                   "reason" : "no such index",                    "resource.type" : "index_or_alias",                    "resource.id" : "fn3r4343",                    "index_uuid" : "_na_",                    "index" : "fn3r4343"                   },                "status": 404               ]         }         "path": "/myapp/search" } 

as 1 can see, returns http 500 status in payload http 404!

what seeking return this:

{      "message" : "index not found exception",     "status"  : "http 404" } 

and known http 404 exceptions:

{      "message" : "not found",     "status"  : "http 404" } 

is there practice / mechanism use restcontrolleradvice catch type of exception , customize response json format readable / useful client using rest api?

this post isn't specific elastic search seeking how trying use @restcontrolleradvice handle type of exception put proper response client app...

the underlying exception being raised org.elasticsearch.client.responseexception (you're using low-level rest client).

so in advice need add handler exception , return underlying status code:

@exceptionhandler(value = { responseexception.class }) public apierrorresponse nohandlerfoundexception(exception ex) {     log.error(ex.getcause().tostring());     int status = ((responseexception) ex).getresponse().getstatusline().getstatuscode();     return new apierrorresponse(status, "<some message depending on status code>"); }