Java 我无法理解“展开贴图”项目中的以下错误

我试图用展开的地图显示全世界的地震数据，但我犯了一个我不理解的错误。请帮我解决这些错误

过去，我曾尝试通过将布尔值设置为true来脱机运行贴图，但没有成功

问题来自课程和作业形式。我在这项任务中遇到了麻烦

Using OpenGLMapDisplay with processing.opengl.PGraphics3D
Exception in thread "Animation Thread" java.lang.NullPointerException
    at module3.EarthquakeCityMap.setup(EarthquakeCityMap.java:102)
    at processing.core.PApplet.handleDraw(PApplet.java:2365)
    at processing.opengl.PJOGL$PGLListener.display(PJOGL.java:873)
    at jogamp.opengl.GLDrawableHelper.displayImpl(GLDrawableHelper.java:690)
    at jogamp.opengl.GLDrawableHelper.display(GLDrawableHelper.java:672)
    at javax.media.opengl.awt.GLCanvas$10.run(GLCanvas.java:1383)
    at jogamp.opengl.GLDrawableHelper.invokeGLImpl(GLDrawableHelper.java:1277)
    at jogamp.opengl.GLDrawableHelper.invokeGL(GLDrawableHelper.java:1131)
    at javax.media.opengl.awt.GLCanvas$11.run(GLCanvas.java:1394)
    at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:301)
    at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:758)
    at java.awt.EventQueue.access$500(EventQueue.java:97)
    at java.awt.EventQueue$3.run(EventQueue.java:709)
    at java.awt.EventQueue$3.run(EventQueue.java:703)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:74)
    at java.awt.EventQueue.dispatchEvent(EventQueue.java:728)
    at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:205)
    at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:116)
    at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:105)
    at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101)
    at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:93)
    at java.awt.EventDispatchThread.run(EventDispatchThread.java:82)

这是个例外

Exception in thread "Animation Thread" java.lang.NullPointerException

这就是

at module3.EarthquakeCityMap.setup(EarthquakeCityMap.java:102)

---

因此，您需要进入EarthquakeCityMap.java，第102行，找到可能导致空指针异常的原因

亲爱的Brandon，这是第102forMarker mk:markers{if int mk.getPropertyyear>2000{mk.setColoryellow；}行{mk.setColorgray；}但是我是这方面的初学者，我不知道它接受和返回什么类型的参数，所以如果我们遍历一个列表，我们需要确保它不为null ifmarkers！=null，以及mk.getPropertyyear的结果，我们还需要确保在将其转换为int之前不为null，并检查它是否可以转换为int ifmk.getPropertyyear！=null&&mk.getPropertyyear instanceOf inti如果这是解决问题的方法，请将其标记为答案，或者如果答案不同，请将答案发布到问题并标记为已回答

at module3.EarthquakeCityMap.setup(EarthquakeCityMap.java:102)