【发布时间】:2016-01-21 23:56:36
【问题描述】:
我正在使用 Apache Spark 的示例代码遵循文档:https://spark.apache.org/docs/latest/ml-features.html#countvectorizer
import java.util.Arrays;
import org.apache.spark.SparkConf;
import org.apache.spark.api.java.JavaSparkContext;
import org.apache.spark.ml.feature.CountVectorizer;
import org.apache.spark.ml.feature.CountVectorizerModel;
import org.apache.spark.sql.DataFrame;
import org.apache.spark.sql.Row;
import org.apache.spark.sql.RowFactory;
import org.apache.spark.sql.SQLContext;
import org.apache.spark.sql.types.*;
public class CountVectorizer_Demo {
public static void main(String[] args) {
SparkConf conf = new SparkConf().setAppName("LDA Online").setMaster(
"local");
JavaSparkContext sc = new JavaSparkContext(conf);
SQLContext sqlContext = new SQLContext(sc);
// Input data: Each row is a bag of words from a sentence or document.
JavaRDD<Row> jrdd = sc.parallelize(Arrays.asList(
RowFactory.create(Arrays.asList("a", "b", "c")),
RowFactory.create(Arrays.asList("a", "b", "b", "c", "a"))
));
StructType schema = new StructType(new StructField [] {
new StructField("text", new ArrayType(DataTypes.StringType, true), false, Metadata.empty())
});
DataFrame df = sqlContext.createDataFrame(jrdd, schema);
// fit a CountVectorizerModel from the corpus
CountVectorizerModel cvModel = new CountVectorizer()
.setInputCol("text")
.setOutputCol("feature")
.setVocabSize(3)
.setMinDF(2) // a term must appear in more or equal to 2 documents to be included in the vocabulary
.fit(df);
// alternatively, define CountVectorizerModel with a-priori vocabulary
CountVectorizerModel cvm = new CountVectorizerModel(new String[]{"a", "b", "c"})
.setInputCol("text")
.setOutputCol("feature");
cvModel.transform(df).show();
}
}
但我收到错误消息:
15/10/22 23:04:20 INFO BlockManagerMasterActor: 使用 703.6 MB RAM,BlockManagerId(, localhost, 56882) 注册块管理器 localhost:56882 15/10/22 23:04:20 INFO BlockManagerMaster:已注册的 BlockManager 线程“主”java.lang.NoClassDefFoundError 中的异常:org/apache/spark/sql/catalyst/InternalRow 在 org.apache.spark.ml.feature.CountVectorizerParams$class.validateAndTransformSchema(CountVectorizer.scala:72) 在 org.apache.spark.ml.feature.CountVectorizer.validateAndTransformSchema(CountVectorizer.scala:107) 在 org.apache.spark.ml.feature.CountVectorizer.transformSchema(CountVectorizer.scala:168) 在 org.apache.spark.ml.PipelineStage.transformSchema(Pipeline.scala:62) 在 org.apache.spark.ml.feature.CountVectorizer.fit(CountVectorizer.scala:130) 在 main.CountVectorizer_Demo.main(CountVectorizer_Demo.java:39) 引起:java.lang.ClassNotFoundException:org.apache.spark.sql.catalyst.InternalRow 在 java.net.URLClassLoader$1.run(URLClassLoader.java:366) 在 java.net.URLClassLoader$1.run(URLClassLoader.java:355) 在 java.security.AccessController.doPrivileged(本机方法) 在 java.net.URLClassLoader.findClass(URLClassLoader.java:354) 在 java.lang.ClassLoader.loadClass(ClassLoader.java:425) 在 sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:308) 在 java.lang.ClassLoader.loadClass(ClassLoader.java:358) ... 6 更多
提前致谢。
【问题讨论】:
标签: java apache-spark apache-spark-mllib