老师，请问是2019.3.4版本的IDea不可以吗

我通过官网搭建项目时，JavaBoot都是高版本不是跟老师一样的版本

我该怎么解决呢

public interface GoodsESRepository extends ElasticsearchRepository<GoodsES,Long> {

这里面的泛型第二个是什么意思

老师有Java的api文档安装包么

老师有Java的api文档安装包么

这里带缓冲的read方法的返回值是读取到的字节数吗

老师，为什么我找到了mycode却找不到我的Welcome.java?

老师，这里报空指针是为啥呢？

老师，学习到后面，前面的就忘记了，这正常吗

家人们，踩坑啊，如果是jdk8之后的版本，JDK 8 中有关反射相关的功能自从 JDK 9 开始就已经被限制了，为了兼容原先的版本，需要在运行项目时添加 --add-opens java.base/java.lang=ALL-UNNAMED 选项来开启这种默认不被允许的行为，在那个VM options里，具体的报错信息如下：

Caused by: java.lang.reflect.InaccessibleObjectException: Unable to make protected final java.lang.Class java.lang.ClassLoader.defineClass(java.lang.String,byte[],int,int,java.security.ProtectionDomain) throws java.lang.ClassFormatError accessible: module java.base does not "opens java.lang" to unnamed module @595b007d

老师 1.png 2.png这六张图片课程资料是没有的 要在哪里取呀
课程资料只有微信图片

我在配置类里面也配置登录和登录页的权限了，为啥访问的时候还是报403

他是怎么做到每五个数就换行的，不是很理解

老师，我在进行高可用部署的时候，可以正常运行，并且其他服务也可以正常运行，但是eureka的服务端会爆如下错误(请您有时间的话可以解答一下)：

2023-12-30T20:06:53.437+08:00 ERROR 46409 --- [et_localhost-18] c.n.e.cluster.ReplicationTaskProcessor   : Network level connection to peer localhost; retrying after delay

jakarta.ws.rs.ProcessingException: org.apache.http.conn.HttpHostConnectException: Connect to localhost:8761 [localhost/127.0.0.1, localhost/0:0:0:0:0:0:0:1] failed: Connection refused

at org.glassfish.jersey.apache.connector.ApacheConnector.apply(ApacheConnector.java:531) ~[jersey-apache-connector-3.1.2.jar:na]

at org.glassfish.jersey.client.ClientRuntime.invoke(ClientRuntime.java:300) ~[jersey-client-3.1.2.jar:na]

at org.glassfish.jersey.client.JerseyInvocation.lambda$invoke$0(JerseyInvocation.java:662) ~[jersey-client-3.1.2.jar:na]

at org.glassfish.jersey.client.JerseyInvocation.call(JerseyInvocation.java:697) ~[jersey-client-3.1.2.jar:na]

at org.glassfish.jersey.client.JerseyInvocation.lambda$runInScope$3(JerseyInvocation.java:691) ~[jersey-client-3.1.2.jar:na]

at org.glassfish.jersey.internal.Errors.process(Errors.java:292) ~[jersey-common-3.1.2.jar:na]

at org.glassfish.jersey.internal.Errors.process(Errors.java:274) ~[jersey-common-3.1.2.jar:na]

at org.glassfish.jersey.internal.Errors.process(Errors.java:205) ~[jersey-common-3.1.2.jar:na]

at org.glassfish.jersey.process.internal.RequestScope.runInScope(RequestScope.java:390) ~[jersey-common-3.1.2.jar:na]

at org.glassfish.jersey.client.JerseyInvocation.runInScope(JerseyInvocation.java:691) ~[jersey-client-3.1.2.jar:na]

at org.glassfish.jersey.client.JerseyInvocation.invoke(JerseyInvocation.java:661) ~[jersey-client-3.1.2.jar:na]

at org.glassfish.jersey.client.JerseyInvocation$Builder.method(JerseyInvocation.java:439) ~[jersey-client-3.1.2.jar:na]

at org.glassfish.jersey.client.JerseyInvocation$Builder.post(JerseyInvocation.java:345) ~[jersey-client-3.1.2.jar:na]

at com.netflix.eureka.transport.Jersey3ReplicationClient.submitBatchUpdates(Jersey3ReplicationClient.java:116) ~[eureka-core-jersey3-2.0.1.jar:2.0.1]

at com.netflix.eureka.cluster.ReplicationTaskProcessor.process(ReplicationTaskProcessor.java:80) ~[eureka-core-2.0.1.jar:2.0.1]

at com.netflix.eureka.util.batcher.TaskExecutors$BatchWorkerRunnable.run(TaskExecutors.java:190) ~[eureka-core-2.0.1.jar:2.0.1]

at java.base/java.lang.Thread.run(Thread.java:842) ~[na:na]

Caused by: org.apache.http.conn.HttpHostConnectException: Connect to localhost:8761 [localhost/127.0.0.1, localhost/0:0:0:0:0:0:0:1] failed: Connection refused

at org.apache.http.impl.conn.DefaultHttpClientConnectionOperator.connect(DefaultHttpClientConnectionOperator.java:156) ~[httpclient-4.5.14.jar:4.5.14]

at org.apache.http.impl.conn.PoolingHttpClientConnectionManager.connect(PoolingHttpClientConnectionManager.java:376) ~[httpclient-4.5.14.jar:4.5.14]

at org.apache.http.impl.execchain.MainClientExec.establishRoute(MainClientExec.java:393) ~[httpclient-4.5.14.jar:4.5.14]

at org.apache.http.impl.execchain.MainClientExec.execute(MainClientExec.java:236) ~[httpclient-4.5.14.jar:4.5.14]

at org.apache.http.impl.execchain.ProtocolExec.execute(ProtocolExec.java:186) ~[httpclient-4.5.14.jar:4.5.14]

at org.apache.http.impl.execchain.RetryExec.execute(RetryExec.java:89) ~[httpclient-4.5.14.jar:4.5.14]

at org.apache.http.impl.execchain.RedirectExec.execute(RedirectExec.java:110) ~[httpclient-4.5.14.jar:4.5.14]

at org.apache.http.impl.client.InternalHttpClient.doExecute(InternalHttpClient.java:185) ~[httpclient-4.5.14.jar:4.5.14]

at org.apache.http.impl.client.CloseableHttpClient.execute(CloseableHttpClient.java:72) ~[httpclient-4.5.14.jar:4.5.14]

at org.glassfish.jersey.apache.connector.ApacheConnector.apply(ApacheConnector.java:483) ~[jersey-apache-connector-3.1.2.jar:na]

... 16 common frames omitted

Caused by: java.net.ConnectException: Connection refused

at java.base/sun.nio.ch.Net.pollConnect(Native Method) ~[na:na]

at java.base/sun.nio.ch.Net.pollConnectNow(Net.java:672) ~[na:na]

at java.base/sun.nio.ch.NioSocketImpl.timedFinishConnect(NioSocketImpl.java:554) ~[na:na]

at java.base/sun.nio.ch.NioSocketImpl.connect(NioSocketImpl.java:602) ~[na:na]

at java.base/java.net.SocksSocketImpl.connect(SocksSocketImpl.java:327) ~[na:na]

at java.base/java.net.Socket.connect(Socket.java:633) ~[na:na]

at org.apache.http.conn.socket.PlainConnectionSocketFactory.connectSocket(PlainConnectionSocketFactory.java:75) ~[httpclient-4.5.14.jar:4.5.14]

at org.apache.http.impl.conn.DefaultHttpClientConnectionOperator.connect(DefaultHttpClientConnectionOperator.java:142) ~[httpclient-4.5.14.jar:4.5.14]

... 25 common frames omitted

a啊？