spark-java

spark出现task不能序列化错误的解决方法

血红的双手。 提交于 2021-02-19 08:12:31
Caused by: java.io.NotSerializableException: org.apache.spark.sql.api.java.StructField"的错误 一般是因为在map、filter等的参数使用了外部的变量,但是这个变量不能序列化。特别是当引用了某个类(经常是当前类)的成员函数或变量时,会导致这个类的所有成员(整个类)都需要支持序列化。解决这个问题最常用的方法有: 1.如果可以,将依赖的变量放到map、filter等的参数内部定义。这样就可以使用不支持序列化的类;2.. 如果可以,将依赖的变量独立放到一个小的class中,让这个class支持序列化;这样做可以减少网络传输量,提高效率; 3.如果可以,将被依赖的类中不能序列化的部分使用transient关键字修饰,告诉编译器它不需要序列化。 4.将引用的类做成可序列化的。 我在scala里面调用java的程序,直接实现接口 Serializable public class LogParser extends Common implements java.io.Serializable{ 解决的 来源: oschina 链接: https://my.oschina.net/u/2510243/blog/666333

How to create a fat jar?

风流意气都作罢 提交于 2021-02-18 07:57:50
问题 With SpringBoot, you have the @SpringBootApplication annotation, but what is the equivalent with the neat Java Spark framework? IntelliJ creates a Maven project and I added the spark dependency, but running the install goal, I get a 5 KB jar with no manifest. Not an executable jar. The pom.xml created thus far is as follows: <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http:/

how to deploy war file in spark-submit command (spark)

我们两清 提交于 2021-02-10 06:36:17
问题 I am using spark-submit --class main.Main --master local[2] /user/sampledata/parser-0.0.1-SNAPSHOT.jar to run a java-spark code, is it possible to run this code using war file instead of jar,since i am looking to deploy it on tomcat i tried by war file but it gives class not found exception 来源: https://stackoverflow.com/questions/40734240/how-to-deploy-war-file-in-spark-submit-command-spark

Java file uploading painfully slow

淺唱寂寞╮ 提交于 2021-02-07 18:10:20
问题 I've built a small service which receives images from an Android device and saves them to a Amazon S3 Bucket. The code is pretty simple but is painfully slow. It goes like this: public synchronized static Response postCommentPicture(Response response, Request request){ JsonObject ret = new JsonObject(); OutputStream outputStream; String meepId = request.params(":id"); System.out.println("1"); if(meepId == null){ ret.addProperty("Error", "Missing meep id"); response.body(ret.getAsString());

Java file uploading painfully slow

不问归期 提交于 2021-02-07 18:07:17
问题 I've built a small service which receives images from an Android device and saves them to a Amazon S3 Bucket. The code is pretty simple but is painfully slow. It goes like this: public synchronized static Response postCommentPicture(Response response, Request request){ JsonObject ret = new JsonObject(); OutputStream outputStream; String meepId = request.params(":id"); System.out.println("1"); if(meepId == null){ ret.addProperty("Error", "Missing meep id"); response.body(ret.getAsString());

Java file uploading painfully slow

若如初见. 提交于 2021-02-07 18:06:33
问题 I've built a small service which receives images from an Android device and saves them to a Amazon S3 Bucket. The code is pretty simple but is painfully slow. It goes like this: public synchronized static Response postCommentPicture(Response response, Request request){ JsonObject ret = new JsonObject(); OutputStream outputStream; String meepId = request.params(":id"); System.out.println("1"); if(meepId == null){ ret.addProperty("Error", "Missing meep id"); response.body(ret.getAsString());

Testing Java Spark Microservices app that implements SparkApplication interface

﹥>﹥吖頭↗ 提交于 2020-01-24 15:14:46
问题 I am trying to figure out how to test a web/rest services written in Java Spark and there is not many tutorials on how to do that. It is tricky to find answers due to confusion between Apache Spark and Java Spark . I came across this resource but, I couldn't get it to work the way I had expected. There is also this resource and examples in Java Spark github but they all probably use embedded server. Anyway, Assuming that I have the following service public class RestService implements