SchoolController.java

package io.singh1114.springboottut.school;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;

import java.util.ArrayList;
import java.util.List;

@RestController
public class SchoolController {

    @Autowired
    private SchoolService schoolService;

    @RequestMapping("/schools")
    public List<School> getAllSchools() {
        return schoolService.getAllSchools();
    }

    @RequestMapping(method = RequestMethod.POST, value = "/school")
    public void addSchool(@RequestBody School school) {
        schoolService.addSchool(school);
    }
}

SchoolService.java

package io.singh1114.springboottut.school;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.util.ArrayList;
import java.util.List;

@Service
public class SchoolService {
    @Autowired
    private SchoolRepository schoolRepository;

    public List<School> getAllSchools() {
        List<School> schools = new ArrayList<>();
        schoolRepository.findAll()
                .forEach(schools::add);
        return schools;
    }

    public void addSchool(School school) {
        schoolRepository.save(school);
    }
}