title: validating json using constraints annotations is not working
body: <p>I am trying to validate a json when deserialize it using constraints annotations  but it doesn't seem to work. for example </p>
  
  <pre><code>import com.fasterxml.jackson.annotation.JsonProperty;
  import javax.validation.constraints.Min;
  import javax.validation.constraints.NotNull;
  
  public class SimpleFooRequest {
  
      @NotNull
      @JsonProperty(value = "count")
      @Min(value = 100,message = "must be min 10")
      private  Integer count;
  
      @NotNull
      private String name;
      public String getName() {return name; }
      public void setName(String name) { this.name = name; }
      public Integer getCount() {return count;}
      public void setCount(Integer count) {this.count = count;}
  }
  </code></pre>
  
  <p>when trying to unmarshal the json</p>
  
  <pre><code>@Test
  public void testFooRequest() throws Exception
  {
    String fooJson = {"count":-10}
    ObjectMapper mapper = new ObjectMapper()
    SimpleFooRequest request = mapper.readValue(fooJson,SimpleFooRequest.class);
    assert request.getCount().equals(-10);//expected fail but it pass !!!
  }
  </code></pre>
  
  <p>it seems to pass although I expected that the assertion will fail due to the count min value limitation . I also tried to put the annotations on the setters but got same results </p>
  
  <p>I have <code>&lt;mvc:annotation-driven /&gt;</code> and <code>hibernate-validator-4.3.1.Final.jar</code> in my dependencies
  I know that I can create custom validator but I thought that for simple validations I can use the annotations . 
  what do I need to do to make it work ? </p>