我的java代码
public class Recipe {
public static class TokenizerMapper extends Mapper<Object, Text, Text, IntWritable>{
private final static IntWritable one = new IntWritable(1);
private Text word = new Text();
Gson gson = new Gson();
public void map(Object key, Text value, Context context ) throws IOException, InterruptedException {
Roo roo=gson.fromJson(value.toString(), Roo.class);
if (roo.manner_of_death != null) {
word.set(roo.manner_of_death);
} else {
word.set("none");
}
context.write(word, one);
}
}
public static class IntSumReducer
extends Reducer<Text,IntWritable,Text,IntWritable> {
private IntWritable result = new IntWritable();
public void reduce(Text key, Iterable<IntWritable> values, Context context) throws IOException, InterruptedException {
int sum = 0;
for (IntWritable val : values) {
sum += val.get();
}
result.set(sum);
context.write(key, result);
}
}
public static void main(String[] args) throws Exception {
Configuration conf = new Configuration();
String[] otherArgs = new GenericOptionsParser(conf, args).getRemainingArgs();
if (otherArgs.length != 2) {
System.err.println("Usage: recipe <in> <out>");
System.exit(2);
}
@SuppressWarnings("deprecation")
Job job = new Job(conf, "Recipe");
job.setJarByClass(Recipe.class);
job.setMapperClass(TokenizerMapper.class);
job.setCombinerClass(IntSumReducer.class);
job.setReducerClass(IntSumReducer.class);
job.setOutputKeyClass(Text.class);
job.setOutputValueClass(IntWritable.class);
FileInputFormat.addInputPath(job, new Path(otherArgs[0]));
FileOutputFormat.setOutputPath(job, new Path(otherArgs[1]));
// FileInputFormat.addInputPath(job, new Path("hdfs://127.0.0.1:9000/in"));
// FileOutputFormat.setOutputPath(job, new Path("hdfs://127.0.0.1:9000/out"));
System.exit(job.waitForCompletion(true) ? 0 : 1);
// job.submit();
}
}
class Id
{
public String oid;
}
class Roo
{
public Id _id ;
public String resident_status;
public String month_of_death;
public String sex;
public String marital_status;
public String manner_of_death;
public String autopsy;
public String race;
}
我的json
{
"_id" : ObjectId("5bfc49155fa79a44dca1f9b9"),
"resident_status" : "1",
"month_of_death" : "06",
"sex" : "M",
"marital_status" : "M",
"manner_of_death" : "7",
"autopsy" : "N",
"race" : "02"
}
{
"_id" : ObjectId("5bfc49155fa79a44dca1f56c"),
"resident_status" : "1",
"month_of_death" : "03",
"sex" : "F",
"marital_status" : "D",
"manner_of_death" : "7",
"autopsy" : "N",
"race" : "01"
}
除id外,所有字段均为字符串
我的错误
18/11/26 18:02:55 info mapreduce.job:task id:attempt\u 1543189350698\u 0010\u m\u000000\u 0,status:failed error:com.google.gson.jsonsyntaxception:java.io.eofexception:com.google.gson.fromjson(gson)第1行第3列输入结束。java:813)
18/11/26 18:02:55 info mapreduce.job:任务id:尝试\u 1543189350698 \u 0010 \u m \u000001 \u 0,状态:失败错误:com.google.gson.jsonsyntaxception:java.lang.illegalstateexception:应为begin \u对象,但在第1行为字符串
1条答案
按热度按时间2nbm6dog1#
当你这么做的时候,
你告诉gson它正试图解析这种类型的对象
这不是您所拥有的,而且您没有有效的json,因为
ObjectId
没有引号。第二个问题-mapreduce默认为读取单行数据,如果输入文件只有两行这样就可以了,但是json仍然应该是有效的