引言

之前在百度、CSDN上查询了各种方法,一直都是空指针异常,原因就是static问题。
先上图。
SpringMVC-Utils-Wrong
之前把service层用@PostConstruct赋值后就直接用静态去获取成Settings就是这里出的问题。

解决

对于定义的Static变量赋值问题应该把调用的service层以及获取数据全部放在init初始化里。就不会报错。

对于方法而言就直接调用就行。下面是代码

@Component
public class MailConfig {

    @Autowired
    private SettingsService settingsService;
    public static MailConfig mailConfig;

    private static final String PROPERTIES_DEFAULT = "mailConfig.properties";
    public static String host;
    public static Integer port;
    public static String userName;
    public static String passWord;
    public static String emailForm;
    public static String timeout;
    public static String personal;
    public static Properties properties;

    @PostConstruct
    public void init(){
        mailConfig = this;
        mailConfig.settingsService = this.settingsService;
        try {
            MailSettings ms = JSON.parseObject(mailConfig.settingsService.getSettings().getMailSettings(), MailSettings.class);
            host = ms.getMailHost();
            port = new Integer(ms.getMailPort());
            userName = ms.getMailUsername();
            passWord = ms.getMailPassword();
            emailForm = ms.getMailUsername();
            timeout = ms.getMailTimeout();
            personal = ms.getPersonal();
        }catch (Exception e) {
            e.printStackTrace();
        }
    }
    
    public static void xx(){
           mailConfig.settingsService.xx();
    }

}