userName=root
password=root
url=www.zpl.com

public class DataSourceModel {

    private String userName;
    private String password;
    private String url;

    @Override
    public boolean equals(Object o) {
        if (this == o)
            return true;
        if (o == null || getClass() != o.getClass())
            return false;
        DataSourceModel that = (DataSourceModel) o;
        return Objects.equals(userName, that.userName) && Objects.equals(password, that.password) && Objects.equals(url, that.url);
    }

    @Override
    public int hashCode() {
        return Objects.hash(userName, password, url);
    }

    @Override
    public String toString() {
        return "DataSourceModel{" +
                "userName='" + userName + '\'' +
                ", password='" + password + '\'' +
                ", url='" + url + '\'' +
                '}';
    }

    public String getUserName() {
        return userName;
    }

    public void setUserName(String userName) {
        this.userName = userName;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }

    public String getUrl() {
        return url;
    }

    public void setUrl(String url) {
        this.url = url;
    }
}

public class DataSourceModelTest {

    @Test
    public void test1() throws Exception {

        //创建一个对象，用于赋值操作
        DataSourceModel model = new DataSourceModel();

        //加载配置文件（）
        InputStream inputStream = Thread.currentThread().getContextClassLoader().getResourceAsStream("db.propertise");
        Properties properties = new Properties();
        //使用缓存流进行加载
        properties.load(new BufferedInputStream(inputStream));

        //获取配置类的Class对象对应的所有方法
        Method[] methods = DataSourceModel.class.getMethods();

        for (Method method : methods) {
            //获取方法名称
            String methodName = method.getName();

            //判断方法前缀是否是set开头
            if (methodName.startsWith("set")) {

                //获取userName中的serName
                String afterName = methodName.substring(4);

                //获取属性第一个字母，也就是setUserName中的U
                String firstName = methodName.substring(3, 4);

                String newName = firstName.toLowerCase() + afterName;

                String property = properties.getProperty(newName);

                if (!Objects.isNull(property)) {
                    //获取方法形参类型
                    Class<?>[] parameterTypes = method.getParameterTypes();
                    String sn = parameterTypes[0].getSimpleName();

                    Object arg = null;
                    //判断属于那种数据类型
                    if (sn.equals("int") || sn.equals("Integer")) {
                        arg = Integer.parseInt(property);
                    } else if (sn.equals("long") || sn.equals("Long")) {
                        arg = Long.parseLong(property);
                    } else if (sn.equals("double") || sn.equals("Double")) {
                        arg = Double.parseDouble(property);
                    } else if (sn.equals("boolean") || sn.equals("Boolean")) {
                        arg = Boolean.parseBoolean(property);
                    } else if (sn.equals("float") || sn.equals("Float")) {
                        arg = Float.parseFloat(property);
                    } else if (sn.equals("String")) {
                        arg = property;
                    } else {
                        continue;
                    }

                    //反射赋值
                    method.invoke(model, arg);
                }
            }

        }

        //输出
        System.out.println("model = " + model);

    }
}