package com.github.yongzhizhan.draftbox.model;

import javax.validation.constraints.Size;

/**
 * 带验证的对象
 * @author zhanyongzhi
 */public class Foo {
  private String validString;

  @Size(min = 1, max = 5)
  public String getValidString() {
    return validString;
  }

  public void setValidString(final String vValidString) {
    validString = vValidString;
  }
}

@ResponseBody@RequestMapping(value = "validObject", method = RequestMethod.POST)
@ResponseStatus(HttpStatus.OK)
public String validObject(
    @RequestBody()
    @Valid Foo vFoo, BindingResult vBindingResult){

  return vFoo.getValidString();
}

@ResponseBody@RequestMapping(value = "validString", method = RequestMethod.GET)
@ResponseStatus(HttpStatus.OK)
public String validString(
    @RequestParam(value = "str", defaultValue = "")
    String vStr){

  return vStr;
}

package com.github.yongzhizhan.draftbox.controller;

import org.springframework.context.annotation.Bean;
import org.springframework.http.HttpStatus;
import org.springframework.stereotype.Component;
import org.springframework.validation.beanvalidation.MethodValidationPostProcessor;
import org.springframework.web.bind.annotation.ControllerAdvice;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.bind.annotation.ResponseStatus;

import javax.validation.ValidationException;

@ControllerAdvice
@Component
public class GlobalExceptionHandler {
  @Bean
  public MethodValidationPostProcessor methodValidationPostProcessor() {
    return new MethodValidationPostProcessor();
  }

  @ExceptionHandler
  @ResponseBody
  @ResponseStatus(HttpStatus.BAD_REQUEST)
  public String handle(ValidationException exception) {
    System.out.println("bad request, " + exception.getMessage());
    return "bad request, " + exception.getMessage();
  }
}

package com.github.yongzhizhan.draftbox.controller;

import com.github.yongzhizhan.draftbox.model.Foo;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.http.HttpStatus;
import org.springframework.validation.BindingResult;
import org.springframework.validation.annotation.Validated;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.bind.annotation.ResponseStatus;
import org.springframework.web.bind.annotation.RestController;

import javax.validation.Valid;
import javax.validation.constraints.Size;

@RestController
@SuppressWarnings("UnusedDeclaration")
@Validated
public class IndexController {
  @ResponseBody
  @RequestMapping(value = "validString", method = RequestMethod.GET)
  @ResponseStatus(HttpStatus.OK)
  public String validString(
      @RequestParam(value = "str", defaultValue = "")
      @Size(min = 1, max = 3)
      String vStr){

    return vStr;
  }
}