POST JSON in body request with Jersey
Ich habe ein dynamisches Java-Webprojekt (das auf einem lokalen Anwendungsserver, Tomcat 7, bereitgestellt wird), das Jersey zum Erstellen von REST-APIs verwendet.
Ich verwende keine Tools zur Build-Automatisierung (daher werden meine Bibliotheken zum Build-Pfad hinzugefügt und das Servlet wird in die Datei "web.xml" eingefügt).
Die Bibliotheken, die ich benutze, sind:
asm-3.1.jar
gson-2.2.1.jar
jersey-client-1.0.3.jar
jersey-core-1.0.3.jar
jersey-json-1.18.jar
jersey-server-1.0.3.jar
jettison-1.1.jar
jsr311-api-1.0.jar
mysql-connector-java-5.0.8-bin.jar
Meine web.xml ist die folgende:
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" id="WebApp_ID" version="2.5">
<display-name>UserAccount</display-name>
<servlet>
<servlet-name>ServletAdaptor</servlet-name>
<servlet-class>com.sun.jersey.server.impl.container.servlet.ServletAdaptor</servlet-class>
<init-param>
<param-name>com.sun.jersey.api.json.POJOMappingFeature</param-name>
<param-value>true</param-value>
</init-param>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>ServletAdaptor</servlet-name>
<url-pattern>/rest/*</url-pattern>
</servlet-mapping>
</web-app>
Die Anwendung interagiert mit einer MySQL-Datenbank. Das Szenario sieht folgendermaßen aus: Die Datenbank enthält eine Benutzerkontentabelle mit dem Namen Benutzer. Die Spalten sind id, name, username und password.
Ich habe eine POST-Methode, um zu überprüfen, ob ein Konto (Benutzername + Passwort) gültig ist. (Benutzername und Passwort als Header-Parameter übergeben)http: // localhost: 8080 / UserAccount / rest / login / doLogin und die Überschriften: Benutzername: x Passwort: 1234
@POST
@Path("/doLogin")
@Produces(MediaType.APPLICATION_JSON)
public String doLogin(@HeaderParam("username") String uname, @HeaderParam("password") String pwd){
String response = "";
if(checkCredentials(uname, pwd)){
response = Utility.constructJSON("login",true);
}else{
response = Utility.constructJSON("login", false, "Incorrect Email or Password");
}
return response;
}
Wie Sie sehen, erzeugt die Antwort eine JSON mit true oder false, basierend darauf, ob das Benutzerkonto gültig ist oder nicht. Und bis jetzt funktioniert es gut. Es funktioniert gut, auch ein GET zu machen und die Parameter als Abfrageparameter zu übergeben (aber das ist nicht der Punkt).
Jetzt versuche ich einen POST durchzuführen, übergebe aber dieses Mal den Benutzernamen und das Passwort in einen JSON-Body:
{
"username":"x",
"password":"1234"
}
Dafür habe ich eine Klasse namens User.java:@ erstel
@XmlRootElement()
@XmlAccessorType(XmlAccessType.FIELD)
public class User implements Serializable {
/**
*
*/
private static final long serialVersionUID = 1L;
@XmlElement(name="username")
private String username;
@XmlElement(name="password")
private String password;
public String getUsername() {
return username;
}
public String getPassword() {
return password;
}
public void setUsername(String username) {
this.username = username;
}
public void setPassword(String password) {
this.password = password;
}
@Override
public String toString() {
// TODO Auto-generated method stub
return "username: " + username;
}
}
Und ich habe eine Methode erstellt:
//pass the arguments as JSON body
@POST
// Path: http://localhost:8080/UserAccount/rest/login/asklogin
@Path("/askLogin")
// Produces JSON as response
@Consumes(MediaType.APPLICATION_JSON)
@Produces(MediaType.APPLICATION_JSON)
public Response askLogin(User user) {
System.out.println("Inside POST askLogin");
if(checkCredentials(user.getUsername(), user.getPassword())) {
return Response.ok().build();
} else {
return Response.serverError().build();
}
}
Ich teste die API mit Advanced Rest Client von Google Chrome und REST Easy von Firefox.
Ich habe auch eine Klasse erstellt, die den MessageBodyReader wie folgt implementiert:
@Provider
public class UserBeanMessageBodyReader implements MessageBodyReader<User> {
//used for MessageBodyReader
@Override
public boolean isReadable(Class<?> type, Type genericType, Annotation[] annotations,
MediaType mediaType) {
return type == User.class;
}
@Override
public User readFrom(Class<User> type, Type genericType, Annotation[] annotations,
MediaType mediaType, MultivaluedMap<String, String> httpHeaders,
InputStream entityStream) throws IOException, WebApplicationException {
try {
JAXBContext jaxbContext = JAXBContext.newInstance(User.class);
User user = (User) jaxbContext.createUnmarshaller().unmarshal(entityStream);
return user;
} catch (JAXBException jaxbException) {
jaxbException.printStackTrace();
System.out.println("Error deserializing a User" + jaxbException);
}
return null;
}
}
Nach dem Debuggen tritt das Problem hier auf:
User user = (User) jaxbContext.createUnmarshaller().unmarshal(entityStream);
und es geht um die catch-Anweisung.
Der Stacktrace ist der folgende:
INFO: Server startup in 1239 ms
javax.xml.bind.UnmarshalException
- with linked exception:
[org.xml.sax.SAXParseException; lineNumber: 1; columnNumber: 1; Content is
not allowed in prolog.]
at javax.xml.bind.helpers.AbstractUnmarshallerImpl.createUnmarshalException(AbstractUnmarshallerImpl.java:335)
at com.sun.xml.internal.bind.v2.runtime.unmarshaller.UnmarshallerImpl.createUnmarshalException(UnmarshallerImpl.java:563)
at com.sun.xml.internal.bind.v2.runtime.unmarshaller.UnmarshallerImpl.unmarshal0(UnmarshallerImpl.java:249)
at com.sun.xml.internal.bind.v2.runtime.unmarshaller.UnmarshallerImpl.unmarshal(UnmarshallerImpl.java:214)
at javax.xml.bind.helpers.AbstractUnmarshallerImpl.unmarshal(AbstractUnmarshallerImpl.java:157)
at javax.xml.bind.helpers.AbstractUnmarshallerImpl.unmarshal(AbstractUnmarshallerImpl.java:204)
at ro.useraccount.jersey.UserBeanMessageBodyReader.readFrom(UserBeanMessageBodyReader.java:36)
at ro.useraccount.jersey.UserBeanMessageBodyReader.readFrom(UserBeanMessageBodyReader.java:1)
at com.sun.jersey.spi.container.ContainerRequest.getEntity(ContainerRequest.java:393)
at com.sun.jersey.server.impl.model.method.dispatch.EntityParamDispatchProvider$EntityInjectable.getValue(EntityParamDispatchProvider.java:139)
at com.sun.jersey.server.impl.inject.InjectableValuesProvider.getInjectableValues(InjectableValuesProvider.java:43)
at com.sun.jersey.server.impl.model.method.dispatch.AbstractResourceMethodDispatchProvider$EntityParamInInvoker.getParams(AbstractResourceMethodDispatchProvider.java:126)
at com.sun.jersey.server.impl.model.method.dispatch.AbstractResourceMethodDispatchProvider$ResponseOutInvoker._dispatch(AbstractResourceMethodDispatchProvider.java:173)
at com.sun.jersey.server.impl.model.method.dispatch.ResourceJavaMethodDispatcher.dispatch(ResourceJavaMethodDispatcher.java:67)
at com.sun.jersey.server.impl.uri.rules.HttpMethodRule.accept(HttpMethodRule.java:163)
at com.sun.jersey.server.impl.uri.rules.RightHandPathRule.accept(RightHandPathRule.java:111)
at com.sun.jersey.server.impl.uri.rules.ResourceClassRule.accept(ResourceClassRule.java:71)
at com.sun.jersey.server.impl.uri.rules.RightHandPathRule.accept(RightHandPathRule.java:111)
at com.sun.jersey.server.impl.uri.rules.RootResourceClassesRule.accept(RootResourceClassesRule.java:63)
at com.sun.jersey.server.impl.application.WebApplicationImpl._handleRequest(WebApplicationImpl.java:654)
at com.sun.jersey.server.impl.application.WebApplicationImpl.handleRequest(WebApplicationImpl.java:612)
at com.sun.jersey.server.impl.application.WebApplicationImpl.handleRequest(WebApplicationImpl.java:603)
at com.sun.jersey.spi.container.servlet.WebComponent.service(WebComponent.java:309)
at com.sun.jersey.spi.container.servlet.ServletContainer.service(ServletContainer.java:425)
at com.sun.jersey.spi.container.servlet.ServletContainer.service(ServletContainer.java:590)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:723)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:293)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:861)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:612)
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:503)
at java.lang.Thread.run(Thread.java:745)
Caused by: org.xml.sax.SAXParseException; lineNumber: 1; columnNumber: 1; Content is not allowed in prolog.
at com.sun.org.apache.xerces.internal.util.ErrorHandlerWrapper.createSAXParseException(ErrorHandlerWrapper.java:203)
at com.sun.org.apache.xerces.internal.util.ErrorHandlerWrapper.fatalError(ErrorHandlerWrapper.java:177)
at com.sun.org.apache.xerces.internal.impl.XMLErrorReporter.reportError(XMLErrorReporter.java:400)
at com.sun.org.apache.xerces.internal.impl.XMLErrorReporter.reportError(XMLErrorReporter.java:327)
at com.sun.org.apache.xerces.internal.impl.XMLScanner.reportFatalError(XMLScanner.java:1437)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl$PrologDriver.next(XMLDocumentScannerImpl.java:999)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl.next(XMLDocumentScannerImpl.java:606)
at com.sun.org.apache.xerces.internal.impl.XMLNSDocumentScannerImpl.next(XMLNSDocumentScannerImpl.java:118)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanDocument(XMLDocumentFragmentScannerImpl.java:510)
at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(XML11Configuration.java:848)
at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(XML11Configuration.java:777)
at com.sun.org.apache.xerces.internal.parsers.XMLParser.parse(XMLParser.java:141)
at com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.parse(AbstractSAXParser.java:1213)
at com.sun.org.apache.xerces.internal.jaxp.SAXParserImpl$JAXPSAXParser.parse(SAXParserImpl.java:643)
at com.sun.xml.internal.bind.v2.runtime.unmarshaller.UnmarshallerImpl.unmarshal0(UnmarshallerImpl.java:243)
... 35 more
Error deserializing a Userjavax.xml.bind.UnmarshalException
- with linked exception:
[org.xml.sax.SAXParseException; lineNumber: 1; columnNumber: 1; Content is not allowed in prolog.]
Inside POST askLogin
Oct 06, 2016 8:57:27 AM org.apache.catalina.core.StandardWrapperValve invoke
SEVERE: Servlet.service() for servlet ServletAdaptor threw exception
java.lang.NullPointerException
at ro.useraccount.jersey.Login.askLogin(Login.java:67)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:497)
at com.sun.jersey.server.impl.model.method.dispatch.AbstractResourceMethodDispatchProvider$ResponseOutInvoker._dispatch(AbstractResourceMethodDispatchProvider.java:175)
at com.sun.jersey.server.impl.model.method.dispatch.ResourceJavaMethodDispatcher.dispatch(ResourceJavaMethodDispatcher.java:67)
at com.sun.jersey.server.impl.uri.rules.HttpMethodRule.accept(HttpMethodRule.java:163)
at com.sun.jersey.server.impl.uri.rules.RightHandPathRule.accept(RightHandPathRule.java:111)
at com.sun.jersey.server.impl.uri.rules.ResourceClassRule.accept(ResourceClassRule.java:71)
at com.sun.jersey.server.impl.uri.rules.RightHandPathRule.accept(RightHandPathRule.java:111)
at com.sun.jersey.server.impl.uri.rules.RootResourceClassesRule.accept(RootResourceClassesRule.java:63)
at com.sun.jersey.server.impl.application.WebApplicationImpl._handleRequest(WebApplicationImpl.java:654)
at com.sun.jersey.server.impl.application.WebApplicationImpl.handleRequest(WebApplicationImpl.java:612)
at com.sun.jersey.server.impl.application.WebApplicationImpl.handleRequest(WebApplicationImpl.java:603)
at com.sun.jersey.spi.container.servlet.WebComponent.service(WebComponent.java:309)
at com.sun.jersey.spi.container.servlet.ServletContainer.service(ServletContainer.java:425)
at com.sun.jersey.spi.container.servlet.ServletContainer.service(ServletContainer.java:590)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:723)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:293)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:861)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:612)
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:503)
at java.lang.Thread.run(Thread.java:745)
Was denkst du