Spark读取HDFS文件,文件格式为GB2312,转换为UTF-8

时间:2023-03-08 17:45:03
package iie.udps.example.operator.spark;

import scala.Tuple2;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapreduce.lib.input.TextInputFormat;
import org.apache.spark.SparkConf;
import org.apache.spark.api.java.JavaPairRDD;
import org.apache.spark.api.java.JavaRDD;
import org.apache.spark.api.java.JavaSparkContext;
import org.apache.spark.api.java.function.FlatMapFunction;
import org.apache.spark.api.java.function.Function;
import org.apache.spark.api.java.function.Function2;
import org.apache.spark.api.java.function.PairFunction; import java.io.UnsupportedEncodingException;
import java.nio.charset.Charset;
import java.util.Arrays;
import java.util.regex.Pattern; /**
* 利用Spark框架读取HDFS文件,文件格式为GB2312,转换为UTF-8,实现WordCount示例
*
* 执行命令:spark-submit --class iie.hadoop.hcatalog.TextFileSparkTest --master
* yarn-cluster /tmp/sparkTest.jar hdfs://192.168.8.101/test/words
* hdfs://192.168.8.101/test/spark/out
*
*
*/
public final class SparkChangeTextCharsetTest {
private static final Pattern SPACE = Pattern.compile(","); @SuppressWarnings("serial")
public static void main(String[] args) throws Exception { if (args.length < 2) {
System.err.println("Usage: JavaWordCount <file>");
System.exit(1);
}
String inputSparkFile = args[0];
String outputSparkFile = args[1]; SparkConf sparkConf = new SparkConf().setAppName("SparkWordCount");
JavaSparkContext ctx = new JavaSparkContext(sparkConf);
Configuration conf = new Configuration();
JavaPairRDD<LongWritable, Text> contents = ctx.newAPIHadoopFile(
inputSparkFile, TextInputFormat.class, LongWritable.class,
Text.class, conf);
JavaRDD<String> lines = contents
.map(new Function<Tuple2<LongWritable, Text>, String>() { public String call(Tuple2<LongWritable, Text> x) {
String lines = null;
try {
lines = new String(x._2().getBytes(), 0, x._2()
.getLength(), "GB2312");
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
}
return lines;
}
});
// JavaRDD<String> changeLines = lines
// .filter(new Function<String, Boolean>() {
// public Boolean call(String s) {
// return s.contains("234");
// }
// });
JavaRDD<String> words = lines
.flatMap(new FlatMapFunction<String, String>() {
@Override
public Iterable<String> call(String s) {
return Arrays.asList(SPACE.split(s));
}
}); JavaPairRDD<String, Integer> ones = words
.mapToPair(new PairFunction<String, String, Integer>() { @Override
public Tuple2<String, Integer> call(String s) {
return new Tuple2<String, Integer>(s, 1);
}
}); JavaPairRDD<String, Integer> counts = ones
.reduceByKey(new Function2<Integer, Integer, Integer>() {
@Override
public Integer call(Integer i1, Integer i2) {
return i1 + i2;
}
}); counts.map(new Function<Tuple2<String, Integer>, String>() {
@Override
public String call(Tuple2<String, Integer> arg0) throws Exception {
return arg0._1.toUpperCase() + ": " + arg0._2;
}
}).saveAsTextFile(outputSparkFile); ctx.stop();
}
}