工作前自动删除已有文件

src/main/java/com/fjy/hadoop/mapreduce/WordCountApp.java

@@ -1,6 +1,7 @@
 package com.fjy.hadoop.mapreduce;
 
 import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.io.LongWritable;
 import org.apache.hadoop.io.Text;
@@ -87,6 +88,14 @@ public class WordCountApp {
         //创建Configuration
         Configuration configuration = new Configuration();
 
+        //清理已存在的输出目录
+        Path outputPath = new Path(args[1]);
+        FileSystem fileSystem = FileSystem.get(configuration);
+        if (fileSystem.exists(outputPath)){
+            fileSystem.delete(outputPath);
+            System.out.println("The exist files had been deleted!");
+        }
+
         //创建作业
         Job job = Job.getInstance(configuration, "wordcount");