How to add third party java jars for use in pyspar

问题:

I have some third party Database client libraries in Java. I want to access them through

java_gateway.py

E.g: to make the client class (not a jdbc driver!) available to the python client via the java gateway:

java_import(gateway.jvm, "org.mydatabase.MyDBClient")

It is not clear where to add the third party libraries to the jvm classpath. I tried to add to compute-classpath.sh but that did nto seem to work: I get

 Py4jError: Trying to call a package

Also, when comparing to Hive: the hive jar files are NOT loaded via compute-classpath.sh so that makes me suspicious. There seems to be some other mechanism happening to set up the jvm side classpath.

回答1:

You can add external jars as arguments to pyspark

pyspark --jars file1.jar,file2.jar

回答2:

You could add the path to jar file using Spark configuration at Runtime.

Here is an example :

conf = SparkConf().set("spark.jars", "/path-to-jar/spark-streaming-kafka-0-8-assembly_2.11-2.2.1.jar")

sc = SparkContext( conf=conf)

Refer the document for more information.

回答3:

You could add --jars xxx.jar when using spark-submit

./bin/spark-submit --jars xxx.jar your_spark_script.py

or set the enviroment variable SPARK_CLASSPATH

SPARK_CLASSPATH='/path/xxx.jar:/path/xx2.jar' your_spark_script.py

your_spark_script.py was written by pyspark API

回答4:

1. Extract the downloaded jar file.
2. Edit system environment variable
   • Add a variable named SPARK_CLASSPATH and set its value to \path\to\the\extracted\jar\file.

Eg: you have extracted the jar file in C drive in folder named sparkts its value should be: C:\sparkts

3. Restart your cluster

回答5:

One more thing you can do is to add the Jar in the pyspark jar folder where pyspark is installed. Usually /python3.6/site-packages/pyspark/jars

Be careful if you are using a virtual environment that the jar needs to go to the pyspark installation in the virtual environment.

This way you can use the jar without sending it in command line or load it in your code.