springmvc返回json数据

1. 加入json的jar包　

jackson-annotations-2.1.5.jar
jackson-core-2.1.5.jar
jackson-databind-2.1.5.jar

2. 发送ajax请求

注意: 这里涉及到springmvc处理静态资源的问题, 比如js文件, 

处理方法: http://www.cnblogs.com/josephcnblog/articles/6593752.html

index.jsp:

<a href="getJson" id="getJson">Get Json</a>

<script type="text/javascript" src="${pageContext.request.contextPath }/script/jquery-1.7.2.min.js"></script>
    <script type="text/javascript">
        $(function() {
            $("#getJson").click(function() {
                // 发送ajax请求
                var url = this.href;
                var args = {"time": new Date()};
                $.post(url, args, function(data) {
                    // 获取json数据
                    for (var i=0; i<data.length; i++) {
                        var id = data[i].id;
                        var lastName = data[i].lastName;
                        alert(id + " : " + lastName);
                    }
                });
            });
        });
    </script>

3. 处理请求, 返回集合

@Controller
public class EmployeeHandler {
    
    @Autowired
    private EmployeeDao employeeDao;
    
    @ResponseBody
    @RequestMapping("/getJson")
    public Collection<Employee> getJson() {
        
        return employeeDao.getAll();
    }
}