有人可以帮我解决这个错误吗？
错误如下
Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: 2
at DCache.main(Dcache.java:197)
第 197 行是DistributedCache.addCacheFile(new URI(args[2]), conf)
Java代码：
import java.io.BufferedReader;
import java.io.FileReader;
import java.io.IOException;
import java.net.URI;
import java.util.HashSet;
import java.util.StringTokenizer;
import org.apache.hadoop.filecache.DistributedCache;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.NullWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapred.FileInputFormat;
import org.apache.hadoop.mapred.FileOutputFormat;
import org.apache.hadoop.mapred.JobClient;
import org.apache.hadoop.mapred.JobConf;
import org.apache.hadoop.mapred.Mapper;
import org.apache.hadoop.mapred.MapReduceBase;
import org.apache.hadoop.mapred.OutputCollector;
import org.apache.hadoop.mapred.Reducer;
import org.apache.hadoop.mapred.Reporter;
import org.apache.hadoop.mapred.TextInputFormat;
import org.apache.hadoop.mapred.TextOutputFormat;
/**
* An example MapReduce program that uses the distributed cache. It uses the NYSE_daily dataset, which has a schem of:
* exchange,stock_symbol,date,stock_price_open,stock_price_high,stock_price_low,stock_price_close,stock_volume,stock_price_adj_close
* and the NYSE_dividends data set, which has a schema of:
* exchange,stock_symbol,date,dividends
* It finds the adjusted closing price for each day that a stock reported a dividend. The dividends data is placed in the distributed
* cache and then loaded into a lookup table so that the join can be done on the map side.
*/
public class DCache {
public static class Pair <T, U> {
public T first;
public U second;
public Pair(T f, U s) {
first = f;
second = s;
}
@Override
public int hashCode() {
return (((this.first == null ? 1 : this.first.hashCode()) * 17)
+ (this.second == null ? 1 : this.second.hashCode()) * 19);
}
@Override
public boolean equals(Object other) {
if(other == null) {
return false;
}
if(! (other instanceof Pair)) {
return false;
}
Pair otherPair = (Pair) other;
boolean examinedFirst = false;
boolean examinedSecond = false;
if (this.first == null) {
if (otherPair.first != null) {
return false;
}
examinedFirst = true;
}
if (this.second == null) {
if (otherPair.second != null) {
return false;
}
examinedSecond = true;
}
if (!examinedFirst && !this.first.equals(otherPair.first)) {
return false;
}
if (!examinedSecond && !this.second.equals(otherPair.second)) {
return false;
}
return true;
}
}
public static class Map extends MapReduceBase implements Mapper<LongWritable, Text, NullWritable, Text> {
private HashSet<Pair<String, String>> lookup = null;
private Path[] localFiles;
public void configure(JobConf job) {
// Get the cached archives/files
try {
localFiles = DistributedCache.getLocalCacheFiles(job);
lookup = new HashSet<Pair<String, String>>();
// Open the file as a local file
FileReader fr = new FileReader(localFiles[0].toString());
BufferedReader d = new BufferedReader(fr);
String line;
while ((line = d.readLine()) != null) {
String[] toks = new String[4];
toks = line.split(",", 4);
// put the stock symbol
lookup.add(new Pair<String, String>(toks[1], toks[2]));
}
fr.close();
} catch (IOException e) {
throw new RuntimeException(e);
}
}
public void map(LongWritable key, Text value, OutputCollector<NullWritable, Text> output, Reporter reporter) throws IOException {
// The first time we are invoked, open up our file from the distributed cache and populate our lookup table
/*
if (lookup == null) {
lookup = new HashSet<Pair<String, String>>();
// Open the file as a local file
FileReader fr = new FileReader(localFiles[0].toString());
BufferedReader d = new BufferedReader(fr);
String line;
while ((line = d.readLine()) != null) {
String[] toks = new String[4];
toks = line.split(",", 4);
// put the stock symbol
lookup.add(new Pair<String, String>(toks[1], toks[2]));
}
fr.close();
}
*/
// Convert the value from Text to a String so we can use the StringTokenizer on it.
String line = value.toString();
// Split the line into fields, using comma as the delimiter
StringTokenizer tokenizer = new StringTokenizer(line, ",");
// We only care about the 2nd, 3rd, and 9th fields (stock_symbol, date, and stock_price_adj_close)
String stock_symbol = null;
String date = null;
String stock_price_adj_close = null;
for (int i = 0; i < 9 && tokenizer.hasMoreTokens(); i++) {
switch (i) {
case 1:
stock_symbol = tokenizer.nextToken();
break;
case 2:
date = tokenizer.nextToken();
break;
case 8:
stock_price_adj_close = tokenizer.nextToken();
break;
default:
tokenizer.nextToken();
break;
}
}
if (stock_symbol == null || date == null || stock_price_adj_close == null) {
// This is a bad record, throw it out
System.err.println("Warning, bad record!");
return;
}
if (stock_symbol.equals("stock_symbol")) {
// NOP, throw out the schema line at the head of each file
return;
}
// Lookup the stock symbol and date in the lookup table
if (lookup.contains(new Pair<String, String>(stock_symbol, date))) {
StringBuilder buf = new StringBuilder(stock_symbol);
buf.append(',').append(date).append(',').append(stock_price_adj_close);
output.collect(NullWritable.get(), new Text(buf.toString()));
}
}
}
public static void main(String[] args) throws Exception {
JobConf conf = new JobConf(DCache.class);
conf.setJobName("DistributedCache_Example");
conf.setOutputKeyClass(NullWritable.class);
conf.setOutputValueClass(Text.class);
conf.setMapperClass(Map.class);
conf.setNumReduceTasks(0);
conf.setInputFormat(TextInputFormat.class);
conf.setOutputFormat(TextOutputFormat.class);
FileInputFormat.setInputPaths(conf, new Path(args[0]));
FileOutputFormat.setOutputPath(conf, new Path(args[1]));
DistributedCache.addCacheFile(new URI(args[2]), conf);
JobClient.runJob(conf);
}
}