echart图表不显示的问题

Question

    <script type="text/javascript">
// 路径配置
require.config({
    paths : {
        echarts : 'http://echarts.baidu.com/build/dist'
    }
});
// 使用
require([ 'echarts', 'echarts/chart/bar' // 使用柱状图就加载bar模块，按需加载
], 
drewEcharts

);
function drewEcharts(ec) {
// 基于准备好的dom，初始化echarts图表
var myChart = ec.init(document.getElementById('main'));

    var option = {
        tooltip : {
            show : true
        },
        legend : {
            data : [ '人数' ]
        },
        xAxis : [ {
            type : 'category',
            data :(function(){
                                var arr=[];
                                    $.ajax({
                                    type : "post",
                                    async : false, //同步执行
                                    url : "bar.do",
                                    data : {},
                                    dataType : "json", //返回数据形式为json
                                    success : function(result) {
                                    if (result) {
                                        /* alter("first"); */
                                           for(var i=0;i<result.length;i++){
                                              console.log(result[i].name);
                                              arr.push(result[i].name);
                                            }    
                                    }

                                },
                                error : function(errorMsg) {
                                    alert("不好意思，图表请求数据失败啦!");
                                    myChart.hideLoading();
                                }
                               })
                               return arr;
                            })() 

        } ],
        yAxis : [ {
            type : 'value'
        } ],
        series : [ {
            "name" : "人数",
            "type" : "bar",
            "data" : (function(){
                                    var arr=[];
                                    $.ajax({
                                    type : "post",
                                    async : false, //同步执行
                                    url : "bar.do",
                                    data : {},
                                    dataType : "json", //返回数据形式为json
                                    success : function(result) {
                                    if (result) {
                                           for(var i=0;i<result.length;i++){
                                              console.log(result[i].num);
                                              arr.push(result[i].num);
                                            }  
                                    }
                                },
                                error : function(errorMsg) {
                                    alert("不好意思，大爷，图表请求数据失败啦!");
                                    myChart.hideLoading();
                                }
                               })
                              return arr;
                        })()

        } ]
    };
    // 为echarts对象加载数据 
    myChart.setOption(option);
}

Answer 1

Connection connection;

public Connection getConnection() {
    try {
        String name = "admin";
        String password = "123456";
        String url = "jdbc:mysql://localhost:3306/todo_ssm";
        Class.forName("com.mysql.jdbc.Driver");
        connection = DriverManager.getConnection(url, name, password);
    } catch (Exception e) {
        e.printStackTrace();
    }
    return connection;
}

public void setConnection(Connection connection) {
    this.connection = connection;
}

public List<barBean> listAll() {
    ArrayList<barBean> list = new ArrayList<barBean>();
    PreparedStatement pstmt = null;
    ResultSet rs = null;
    try {
        pstmt = this.getConnection().prepareStatement("SELECT * FROM records");
        rs = pstmt.executeQuery();
        while (rs.next()) {
            barBean bar = new barBean();
            bar.setName(rs.getString("name"));
            bar.setSum(rs.getInt("sum"));
            list.add(bar);
            System.out.println("连接数据库成功");
        }
    } catch (Exception e) {
        e.printStackTrace();
    } finally {
        try {
            connection.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
    return list;
}

java代码如下，数据是获取到了，就是不显示图表![图片说明](https://img-ask.csdn.net/upload/201705/24/1495612569_329148.png)