GAE'nin arka uç hizmet insert

Question

benim varlık sınıfı i son nokta sınıfını oluşturulan ve sonra GAE bunu sağlamış

@PersistenceCapable 
public class User { 

    @PrimaryKey 
    @Persistent(valueStrategy = IdGeneratorStrategy.IDENTITY) 
    private Key id; 

    @Persistent 
    private String userName; 

    @Persistent 
    private String password; 

    public User() { 

    } 

    public User(String userName, String password) { 
     this.userName = userName; 

     this.password = password; 

    } 

    public String getUserName() { 
     return userName; 

    } 

    public void setUserName(String userName) { 
     this.userName = userName; 

    } 

    public String getPassword() { 
     return password; 

    } 

    public void setPassword(String password) { 
     this.password = password; 

    } 

    public Key getId() { 
     return id; 
    } 
} 

olduğunu çalışmaz.

ben yöntemi UserEndpoint.containsUser(UserEndpoint.java:152) çağrıldığında bir NullPointerException var api kaşif

https://apis-explorer.appspot.com/apis-explorer/?base=https://ig-project-1280.appspot.com/_ah/api#p/userendpoint/v1/userendpoint.insertUser?_h=4&resource=%257B%250A++%2522password%2522%253A+%2522welcome1%2522%252C%250A++%2522userName%2522%253A+%2522vik.ceo%2540gmail.com%2522%250A%257D& 

and did the insert operation. The error come up is: 
com.google.api.server.spi.SystemService invokeServiceMethod: exception occurred while calling backend method 
java.lang.NullPointerException 
    at org.datanucleus.api.jpa.JPAEntityManager.find(JPAEntityManager.java:318) 
    at org.datanucleus.api.jpa.JPAEntityManager.find(JPAEntityManager.java:256) 
    at photography.viks.app.ig.entity.UserEndpoint.containsUser(UserEndpoint.java:152) 
    at photography.viks.app.ig.entity.UserEndpoint.insertUser(UserEndpoint.java:99) 
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) 
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) 
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) 
    at java.lang.reflect.Method.invoke(Method.java:44) 
    at com.google.api.server.spi.SystemService.invokeServiceMethod(SystemService.java:363) 
    at com.google.api.server.spi.SystemServiceServlet.execute(SystemServiceServlet.java:113) 
    at com.google.api.server.spi.SystemServiceServlet.doPost(SystemServiceServlet.java:71) 
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:637) 
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:717) 
    at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:511) 
    at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1166) 
    at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157) 
    at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157) 
    at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157) 
    at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157) 
    at org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:388) 
    at org.mortbay.jetty.security.SecurityHandler.handle(SecurityHandler.java:216) 
    at org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java:182) 
    at org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java:765) 
    at org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java:418) 
    at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152) 
    at org.mortbay.jetty.Server.handle(Server.java:326) 
    at org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java:542) 
    at org.mortbay.jetty.HttpConnection$RequestHandler.headerComplete(HttpConnection.java:923) 
    at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:404) 
    at com.google.tracing.TraceContext$TraceContextRunnable.runInContext(TraceContext.java:437) 
    at com.google.tracing.TraceContext$TraceContextRunnable$1.run(TraceContext.java:444) 
    at com.google.tracing.CurrentContext.runInContext(CurrentContext.java:256) 
    at com.google.tracing.TraceContext$AbstractTraceContextCallback.runInInheritedContextNoUnref(TraceContext.java:308) 
    at com.google.tracing.TraceContext$AbstractTraceContextCallback.runInInheritedContext(TraceContext.java:300) 
    at com.google.tracing.TraceContext$TraceContextRunnable.run(TraceContext.java:441) 
    at java.lang.Thread.run(Thread.java:745) 

Answer 1

gitti. Özel Durumunuz, uygulamanızdaki google api uç nokta katmanı tarafından sağlanan arka uç hizmet istisnası sınıfına sarılır. Sadece bu sınıfa ait kodunuzu kontrol edin ve problemi bulacaksınız.