I created a sample OpenAPI spec using SwaggerHub:
https://app.swaggerhub.com/apis/Leejjon/Example/1.0.0
Then I generate a server stub via Export -> Server Stub -> Spring (you can do the same via the url above to get my full code)
I am running on Windows 7 (don't laugh) and Java 11. When doing a mvn clean install I get:
C:/Users/Leejjon/Downloads/spring-server-generated/src/main/java/io/swagger/api/ApiResponseMessage.java:[3,33] package javax.xml.bind.annotation does not exist
This is because Jaxb has been removed since Java 11, so I add the Jaxb API and an implementation to my pom.xml:
<dependency>
<groupId>javax.xml.bind</groupId>
<artifactId>jaxb-api</artifactId>
<version>2.4.0-b180830.0359</version>
</dependency>
<dependency>
<groupId>org.glassfish.jaxb</groupId>
<artifactId>jaxb-runtime</artifactId>
<version>2.4.0-b180830.0438</version>
</dependency>
Now everything compiles and I can run the server using mvn spring-boot:run -Dserver.port=8080. Everything seems fine. The server seems to boot up and logging seems to indicate that it's listening for requests.
See full output here: https://pastebin.com/cDLMV8p0
When visiting http://localhost:8080/ or http://localhost:8080/examples/something I only get 404's. Anyone has a clue how to get this working?
Try opening the application.properties file, look if there is a server.contextPath= variable.
Take this value and put it after your port value but before the resource value from your controller
e.g. :
http://localhost:8080/{yourContextPath}/something/?someRequestParam=someValue
Good luck
I have project used Nashorn Javascript engine. I'm trying to migrate to java11 and also migrate from Nashorn to Graal. I've read here that I can use graal via the standard JDK installation starting from JDK 11. Also I've read there that Graal-SDK are uploaded to Maven central, and that there is Java flag polyglot.js.nashorn-compat for easy migration. So I've used jdk11, add maven dependency to pom.xml and used java flag but when I'm trying to get engine by name "graal.js", I've got null here:
ScriptEngine engine = engineManager.getEngineByName("graal.js")
What I'm missing? How to make it work?
Here is a sample maven project that shows how to run the GraalVM JavaScript engine on JDK11 both through the scripting API and the polyglot API. Hope it helps!
https://github.com/graalvm/graal-js-jdk11-maven-demo
The gist of it is to add the necessary dependencies (graal-sdk, js, js-scriptengine, and optionally profiler and chromeinspector), Run with enabled experimental options and the JVMCI compiler (-XX:+UnlockExperimentalVMOptions -XX:+EnableJVMCI) and upgrade the module path with the graal jar (--upgrade-module-path=${compiler.dir}/compiler.jar) which is also available from maven (org.graalvm.compiler:compiler).
You are missing the following dependencies:
<dependency>
<groupId>org.graalvm.js</groupId>
<artifactId>js-scriptengine</artifactId>
</dependency>
<dependency>
<groupId>org.graalvm.truffle</groupId>
<artifactId>truffle-api</artifactId>
</dependency>
js-scriptengine contains the ScriptEngine implementation: com.oracle.truffle.js.scriptengine.GraalJSScriptEngine.
And the truffle-api is required (you only get the rror message if you instanciate the GraalJSEngineFactory directly:
GraalJSEngineFactory gsf = new GraalJSEngineFactory();
However there seems to be another package missing, as it does not work for me.
I tried to parse an excel file in Java. I used the OSGI framework and I used a karaf container to deploy my application. I found out later that I can parse the file using Apache POI. I tried to use an Osgi wrapper and I put the dependency in the pom file:
<dependency>
<groupId>org.apache.servicemix.bundles</groupId>
<artifactId>org.apache.servicemix.bundles.junit</artifactId>
<version>4.12_1</version>
</dependency>
Using this when I tried parsing the excel file I received the following runtime exception:
Cannot load org.apache.xmlbeans.impl.SchemaTypeSystemImpl: make sure xbean.jar is on the classpath.
After that I added another dependency for xbean, like this:
<dependency>
<groupId>org.apache.servicemix.bundles</groupId>
<artifactId>org.apache.servicemix.bundles.xmlbeans</artifactId>
<version>2.6.0_2</version>
</dependency>
After I added the xbean dependency my bundle has the Installed status because it is missing a dependency from "com.sun.javadoc" and I can't resolve this missing dependency.
How can I add Apache POI in my project? Or how can I parse an excel file more easily?
Thanks.
I have a Maven Java project that uses Mashape Unirest for sending HTTP requests to other URLs. I am currently writing an integration test (using TestNG) that sends a normal HTTP request using Unirest. When I run the integration test through Maven (via the Failsafe plugin), the request is sent out successfully. However, when I try to run the integration test via Eclipse, I keep on getting the following error:
FAILED: getCurrentTimeTest
java.lang.NoSuchFieldError: INSTANCE
at org.apache.http.impl.io.DefaultHttpRequestWriterFactory.<init>(DefaultHttpRequestWriterFactory.java:52)
at org.apache.http.impl.io.DefaultHttpRequestWriterFactory.<init>(DefaultHttpRequestWriterFactory.java:56)
at org.apache.http.impl.io.DefaultHttpRequestWriterFactory.<clinit>(DefaultHttpRequestWriterFactory.java:46)
at org.apache.http.impl.conn.ManagedHttpClientConnectionFactory.<init>(ManagedHttpClientConnectionFactory.java:72)
at org.apache.http.impl.conn.ManagedHttpClientConnectionFactory.<init>(ManagedHttpClientConnectionFactory.java:84)
at org.apache.http.impl.conn.ManagedHttpClientConnectionFactory.<clinit>(ManagedHttpClientConnectionFactory.java:59)
at org.apache.http.impl.conn.PoolingHttpClientConnectionManager$InternalConnectionFactory.<init>(PoolingHttpClientConnectionManager.java:487)
at org.apache.http.impl.conn.PoolingHttpClientConnectionManager.<init>(PoolingHttpClientConnectionManager.java:147)
at org.apache.http.impl.conn.PoolingHttpClientConnectionManager.<init>(PoolingHttpClientConnectionManager.java:136)
at org.apache.http.impl.conn.PoolingHttpClientConnectionManager.<init>(PoolingHttpClientConnectionManager.java:112)
at org.apache.http.impl.client.HttpClientBuilder.build(HttpClientBuilder.java:726)
at com.mashape.unirest.http.options.Options.refresh(Options.java:41)
at com.mashape.unirest.http.options.Options.<clinit>(Options.java:27)
at com.mashape.unirest.http.HttpClientHelper.prepareRequest(HttpClientHelper.java:141)
at com.mashape.unirest.http.HttpClientHelper.requestAsync(HttpClientHelper.java:80)
at com.mashape.unirest.request.BaseRequest.asStringAsync(BaseRequest.java:56)
at ...
I am also able to reproduce this error using a basic Java application script.
I have made sure that the dependencies I am using in my pom.xml file are the latest and greatest, as seen below:
<dependency>
<groupId>com.mashape.unirest</groupId>
<artifactId>unirest-java</artifactId>
<version>1.3.5</version>
</dependency>
<dependency>
<groupId>org.apache.httpcomponents</groupId>
<artifactId>httpclient</artifactId>
<version>4.3.2</version>
</dependency>
<dependency>
<groupId>org.apache.httpcomponents</groupId>
<artifactId>httpasyncclient</artifactId>
<version>4.0</version>
</dependency>
<dependency>
<groupId>org.apache.httpcomponents</groupId>
<artifactId>httpmime</artifactId>
<version>4.3.2</version>
</dependency>
<dependency>
<groupId>org.json</groupId>
<artifactId>json</artifactId>
<version>20140107</version>
</dependency>
<dependency>
<groupId>org.apache.httpcomponents</groupId>
<artifactId>httpcore</artifactId>
<version>4.3.2</version>
</dependency>
I have also checked out the source code of BasicLineFormatter.java, both from the source file downloaded to Eclipse and from Apache's Httpcore Github repo. In the Github repo, notice how the INSTANCE field is defined for the 4.3.x branch and the trunk branch, but not in older branches like 4.2.x. However, I am indeed using version 4.3.2 in my project, so I should be using a JAR file for Httpcore that has the latest version of BasicLineFormatter. I know that, based on the Maven Dependencies JAR files that are in my project, that I am indeed using the latest versions of these Apache dependencies, not the older versions specified as downstream dependencies of my project.
I have checked other various SOF and blog posts about this issue, such as Mashape Unirest Java : java.lang.NoClassDefFoundError and this blog post too, but they all seem to be talking about solving the NoSuchFieldError problem for Android. However, I'm dealing with a standalone Java application, not an Android application.
I am at a loss in determining how to troubleshoot this issue. Anyone have any idea what I need to do?
UPDATE
Instead of showing my test case, I will reduce the illustration of a reproduction of this problem to just a simple one-liner Java application, because the problem exists with any Java application or test case run through Eclipse, not just one particular test:
System.out.println(Unirest.get("http://www.google.com").asStringAsync().get().getBody());
Normally, this should print the HTML of the Google home page, but I instead get the NoSuchFieldError stack trace.
FIXED!
The problem was that the AWS SDK (it's on my classpath because I'm developing for Elastic Beanstalk) had a conflicting JAR file. Using Oleg's solution (thanks BTW), I printed the following output in a unit test:
jar:file:/some/path/aws-java-sdk/1.7.1/third-party/httpcomponents-client-4.2.3/httpcore-4.2.jar!/org/apache/http/message/BasicLineFormatter.class
I'll have to rearrange my classpath so that AWS SDK is no longer conflicting.
The only plausible explanation to this problem is there is an older version of HttpCore on the classpath (unless you also want to consider a possibility of green men from Mars messing with your computer remotely from a flying saucer).
You can add this snippet to your code to find out what jar the class gets picked up from. This might help find out why that jar is on your classpath in the first place.
ClassLoader classLoader = MyClass.class.getClassLoader();
URL resource = classLoader.getResource("org/apache/http/message/BasicLineFormatter.class");
System.out.println(resource);
This basically tells me that in my case the jar resides in the local maven repository and likely to have been added to the classpath by Maven
jar:file:/home/oleg/.m2/repository/org/apache/httpcomponents/httpcore/4.3.1/httpcore-4.3.1.jar!/org/apache/http/message/BasicLineFormatter.class
As already mentioned by previous comments, It's mainly because of the conflicting versions of httpcore jar, the static field INSTANCE is been added to BasicLineFormatter class in versions > 4.3.1, Though you might have added the latest version of the httpcore jar in your dependencies, but its highly possible that other (lower) version of jar is getting picked up.
So, first to confirm that, wrong jar is getting picked up, Use the following line of code -
ClassLoader classLoader = <Your Class>.class.getClassLoader();
URL resource = classLoader.getResource("org/apache/http/message/BasicLineFormatter.class");
System.out.println(resource);
If this prints, the lower version of the jar, then it's confirmed that it's picking the lower version of the httpcore jar (May be from other dependencies of your project),
Solution -
Add following maven/gradle dependencies at the top of dependency list (Or above the other project dependency which caused the conflict) -
<dependency>
<groupId>com.mashape.unirest</groupId>
<artifactId>unirest-java</artifactId>
<version>1.4.5</version>
</dependency>
<dependency>
<groupId>org.apache.httpcomponents</groupId>
<artifactId>httpcore</artifactId>
<version>4.4.1</version>
</dependency>
<dependency>
<groupId>org.apache.httpcomponents</groupId>
<artifactId>httpclient</artifactId>
<version>4.4.1</version>
</dependency>
I faced the same exception using unirest:
java.lang.NoSuchFieldError: INSTANCE
at org.apache.http.impl.io.DefaultHttpRequestWriterFactory.<init>(DefaultHttpRequestWriterFactory.java:52)
at com.mashape.unirest.http.options.Options.refresh(Options.java:55)
at com.mashape.unirest.http.options.Options.<clinit>(Options.java:36)
And found it was due to DefaultConnectionKeepAliveStrategy.INSTANCE; and the conflicting jar was apache-httpcomponents-httpclient.jar in my classpath. Adding this post to help anyone who faces similar exception
I got this Exception: Caused by: java.lang.NoSuchFieldError: INSTANCE
Solution:
This happens if you have two different version classes in your classpath…. […], So I first find that class (one version of class), click that class, select build path, then I click remove from build path.
if you are using aws sdk this error occurs because of dependency mismatch.
To avoid this error do the following:
1.Put the dependecies in the required order aws sdk and the end preferably
2.Add shade plugin to the project
This solved my problem
you can refer to my answer in
HTTPClient Example - Exception in thread "main" java.lang.NoSuchFieldError: INSTANCE
my case is i have httpclient-4.4.1.jar, and httpcore-4.4.1.jar in my class path, but JVM loaded BasicLineFormatter from httpcore-4.0.jar
I am generating a webservice stubusing this statement in java
new TPFServiceStub(webserviceUrl);
I have created a mock service in soap UI at 8088.
The same URL I am passing in the webserviceUrl variable.
All the dependent jars are placed in axis_home.
I am getting this following error.
Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/axiom/om/OMDataSource
at com.arcot.csso.credchangereportsvc.dao.CIWebserviceDAO.getServiceObject
Can you please help me out :)
You have the axiom jar containing the OMDataSource class in your deployment classpath?
I'm guessing the library/framework you've been using to implement your WebService endpoints uses Apache Axiom as SOAP Message Factory. So, you should make sure you have Axiom jar on your classpatch.
You can get the latest binary for Apache Axiom here: http://ws.apache.org/axiom/download.cgi
In case you've been yet another happy user of Maven you can simpply add the following dependency to your pom.xml file:
<dependency>
<groupId>org.apache.ws.commons.axiom</groupId>
<artifactId>axiom</artifactId>
<version>1.2.11</version>
<type>pom</type>
<scope>runtime</scope>
</dependency>