解决静态utils里面注入mapper对象

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项目中需要在一个utils工具类中，调用mapper对象来进行功能实现，然而静态方法里面直接注入会报空指针的错误，网上查了一些资料得出如下解决办法

重点步骤：

1，utils类上面添加@Component注解

2，@Autowired注入需要使用的mapper对象，注意不是静态的

3，创建一个静态的这个utils的对象 private static LayoutNumUtils layoutNumUtils;

4，创建一个init方法，添加@PostConstruct注解，方法内容如下

OK，在接下来的调用中，使用utils的对象来调用对应的mapper对象layoutNumUtils.busiTabLayoutMapper.selectByTabId(tabId);

<span style="font-size:18px;">@Component
public class LayoutNumUtils {
@Autowired
private BusiTabMapper busiTabMapper;
@Autowired
private BusiTabLayoutMapper busiTabLayoutMapper;
private static LayoutNumUtils layoutNumUtils;
@PostConstruct
public void init(){
layoutNumUtils = this;
layoutNumUtils.busiTabMapper = this.busiTabMapper;
layoutNumUtils.busiTabLayoutMapper = this.busiTabLayoutMapper;
}
public static void layoutTypeCheck(Integer tabId){
try {
List<BusiTabLayout> list = layoutNumUtils.busiTabLayoutMapper.selectByTabId(tabId);</span>

@Component

public class LayoutNumUtils {
@Autowired</br>

private  BusiTabMapper busiTabMapper;</br>

@Autowired</br>

private  BusiTabLayoutMapper busiTabLayoutMapper;</br></br>

private static LayoutNumUtils layoutNumUtils;</br></br>

@PostConstruct</br>

public void init(){</br>

	layoutNumUtils = this;</br>

	layoutNumUtils.busiTabMapper = this.busiTabMapper;</br>

	layoutNumUtils.busiTabLayoutMapper = this.busiTabLayoutMapper;</br>

}</br></br>

public static void layoutTypeCheck(Integer tabId){</br>

	try {</br>

		List&lt;BusiTabLayout&gt; list = layoutNumUtils.busiTabLayoutMapper.selectByTabId(tabId);</span></pre><span style="font-size:18px;"><br><br></span></br>