isaacgarza / saml-example Goto Github PK

running the backend application as it's is giving the following error :

org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.springframework.boot.web.servlet.context.AnnotationConfigServletWebServerApplicationContext]: Constructor threw exception; nested exception is java.lang.NoClassDefFoundError: org/springframework/core/metrics/ApplicationStartup
at org.springframework.beans.BeanUtils.instantiateClass(BeanUtils.java:224) ~[spring-beans-5.3.20.jar:5.3.20]
at org.springframework.beans.BeanUtils.instantiateClass(BeanUtils.java:146) ~[spring-beans-5.3.20.jar:5.3.20]
at org.springframework.boot.SpringApplication.createApplicationContext(SpringApplication.java:607) [spring-boot-2.1.4.RELEASE.jar:2.1.4.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:310) [spring-boot-2.1.4.RELEASE.jar:2.1.4.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1260) [spring-boot-2.1.4.RELEASE.jar:2.1.4.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1248) [spring-boot-2.1.4.RELEASE.jar:2.1.4.RELEASE]
at com.example.saml.Application.main(Application.java:25) [classes/:na]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_382]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_382]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_382]
at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_382]
at org.springframework.boot.devtools.restart.RestartLauncher.run(RestartLauncher.java:49) [spring-boot-devtools-2.1.4.RELEASE.jar:2.1.4.RELEASE]
Caused by: java.lang.NoClassDefFoundError: org/springframework/core/metrics/ApplicationStartup
at org.springframework.context.support.AbstractApplicationContext.(AbstractApplicationContext.java:229) ~[spring-context-5.3.20.jar:5.3.20]
at org.springframework.context.support.GenericApplicationContext.(GenericApplicationContext.java:112) ~[spring-context-5.3.20.jar:5.3.20]
at org.springframework.web.context.support.GenericWebApplicationContext.(GenericWebApplicationContext.java:81) ~[spring-web-5.1.6.RELEASE.jar:5.1.6.RELEASE]
at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.(ServletWebServerApplicationContext.java:115) ~[spring-boot-2.1.4.RELEASE.jar:2.1.4.RELEASE]
at org.springframework.boot.web.servlet.context.AnnotationConfigServletWebServerApplicationContext.(AnnotationConfigServletWebServerApplicationContext.java:72) ~[spring-boot-2.1.4.RELEASE.jar:2.1.4.RELEASE]
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) ~[na:1.8.0_382]
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62) ~[na:1.8.0_382]
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) ~[na:1.8.0_382]
at java.lang.reflect.Constructor.newInstance(Constructor.java:423) ~[na:1.8.0_382]
at org.springframework.beans.BeanUtils.instantiateClass(BeanUtils.java:211) ~[spring-beans-5.3.20.jar:5.3.20]
... 11 common frames omitted
Caused by: java.lang.ClassNotFoundException: org.springframework.core.metrics.ApplicationStartup
at java.net.URLClassLoader.findClass(URLClassLoader.java:387) ~[na:1.8.0_382]
at java.lang.ClassLoader.loadClass(ClassLoader.java:418) ~[na:1.8.0_382]
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:352) ~[na:1.8.0_382]
at java.lang.ClassLoader.loadClass(ClassLoader.java:351) ~[na:1.8.0_382]
... 21 common frames omitted

I am new to SAML authentication I am trying to build saml authentcation, where my front-end is using react and bank-end as spring boot application . I am able to authenticate api's of backend but when I am integrating with UI I am getting error.......I want to understand what does this line "start": "ng serve -o --proxy-config proxy.config.json --port 3000"," does in package.json I have tried proxying in my application but its not working. Please help me to understand this