java Spring boot jpa crudrepository nullpointerexception 保存
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时间：2020-11-02 20:24:40 来源:igfitidea点击:
Spring boot jpa crudrepository nullpointerexception to save
提问by kakashi hatake
when to save data and list by restful web service I take this error nullpointerexception ApiRestService.java
何时通过restful web服务保存数据和列表我接受这个错误nullpointerexception ApiRestService.java
package com.twitterservice.service;
@RestController
public class ApiRestService {
private static final Logger logger = LoggerFactory.getLogger(ApiRestService.class);
@Autowired(required = true)
ApiRepository ApiRepo;
TwitterRepository TwitRepo;
@RequestMapping(value = "/rest/twitterapi", method = RequestMethod.POST, produces = "application/json")
@ResponseBody
public ResponseEntity<ApiDomain> saveApiKeys(@RequestBody ApiDomain request) {
ApiRepo.save(request);
return new ResponseEntity<ApiDomain>(request, HttpStatus.OK);
}
@RequestMapping(value = "/rest/twitter", method = RequestMethod.GET)
@SuppressWarnings("empty-statement")
public Iterable<TwitterDomain> getAll() throws TwitterException {
ApiDomain apikeys = ApiRepo.findOne(1L);
ConfigurationBuilder xb = new ConfigurationBuilder();
xb.setDebugEnabled(true)
.setOAuthConsumerKey(apikeys.getConsumerKey())
.setOAuthConsumerSecret(apikeys.getConsumerSecret())
.setOAuthAccessToken(apikeys.getAccessToken())
.setOAuthAccessTokenSecret(apikeys.getAccessTokenSecret());
TwitterFactory tf = new TwitterFactory(xb.build());
twitter4j.Twitter tw = tf.getInstance();
List<Status> statuses = tw.getHomeTimeline();
for (Status a : statuses) {
TwitRepo.save(new TwitterDomain(a.getUser().getName(), a.getText(), "stable"));
}
Iterable<TwitterDomain> lst = TwitRepo.findAll();
return lst;
}
}
ApiDomain.java
ApiDomain.java
package com.twitterservice.dao;
@Entity
public class ApiDomain implements Serializable {
@Id
@GeneratedValue(strategy = GenerationType.AUTO)
private long id;
private String accountName;
private String consumerKey;
private String consumerSecret;
private String accessToken;
private String accessTokenSecret;
public long getId() {
return id;
}
public void setId(long id) {
this.id = id;
}
public String getAccountName() {
return accountName;
}
public void setAccountName(String accountName) {
this.accountName = accountName;
}
public String getConsumerKey() {
return consumerKey;
}
public void setConsumerKey(String consumerKey) {
this.consumerKey = consumerKey;
}
public String getConsumerSecret() {
return consumerSecret;
}
public void setConsumerSecret(String consumerSecret) {
this.consumerSecret = consumerSecret;
}
public String getAccessToken() {
return accessToken;
}
public void setAccessToken(String accessToken) {
this.accessToken = accessToken;
}
public String getAccessTokenSecret() {
return accessTokenSecret;
}
public void setAccessTokenSecret(String accessTokenSecret) {
this.accessTokenSecret = accessTokenSecret;
}
public ApiDomain(String accountName, String consumerKey, String consumerSecret, String accessToken, String accessTokenSecret) {
this.accountName = accountName;
this.consumerKey = consumerKey;
this.consumerSecret = consumerSecret;
this.accessToken = accessToken;
this.accessTokenSecret = accessTokenSecret;
}
public ApiDomain() {
}
}
TwitterDomain
推特域
package com.twitterservice.dao;
@Entity
public class TwitterDomain implements Serializable {
@Id
@GeneratedValue(strategy = GenerationType.AUTO)
private long id;
private String twitteruser;
private String twittertext;
private String status;
public String getTwitteruser() {
return twitteruser;
}
public void setTwitteruser(String twitteruser) {
this.twitteruser = twitteruser;
}
public String getTwittertext() {
return twittertext;
}
public void setTwittertext(String twittertext) {
this.twittertext = twittertext;
}
public String getStatus() {
return status;
}
public void setStatus(String status) {
this.status = status;
}
public TwitterDomain(String twitteruser, String twittertext, String status) {
this.twitteruser = twitteruser;
this.twittertext = twittertext;
this.status = status;
}
public TwitterDomain() {
}
}
myrepository
我的存储库
package com.twitterservice.repository;
import org.springframework.data.repository.CrudRepository;
public interface TwitterRepository extends CrudRepository<TwitterDomain, Long> {
List<TwitterDomain> findByTwittertext(String twittertext);
}
And error when I call to service
当我打电话给服务时出错
java.lang.NullPointerException: null
at com.twitterservice.service.ApiRestService.getAll(ApiRestService.java:71)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:497)
at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:221)
at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:137)
at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:110)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandleMethod(RequestMappingHandlerAdapter.java:776)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:705)
at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:85)
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:959)
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:893)
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:967)
at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:858)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:622)
at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:843)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:291)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:239)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:77)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:239)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:85)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:239)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:219)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:106)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:142)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:88)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:518)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1091)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:668)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1521)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1478)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Thread.java:745)
handle to error this row
处理错误这一行
TwitRepo.save(new TwitterDomain(a.getUser().getName(), a.getText(), "stable"));
回答by Anthony Raymond
This happens because you autowired only the ApiRepositoryfield.
发生这种情况是因为您仅自动装配了该ApiRepository字段。
The @Autowiredapplies to the first below field, not to all fields in the class, you need to add the annotation on every field you want to inject.
在@Autowired适用于第一场下面，不要在类的所有领域，你需要添加要注入的每个字段的注解。
@Autowired(required = true)
private ApiRepository ApiRepo;
@Autowired(required = true)
private TwitterRepository TwitRepo;
