hadoop - 无法在 IDE 内为 Hadoop 项目运行 Maven，但它确实在 IDE 外编译

Question

我下载并安装：

• -马文

• -Cloudera Hadoop

• -IntelliJ IDEA 终极版

• -Tom Whites 的 GitHub 源代码示例：https ://github.com/tomwhite/hadoop-book/

当我在 IntelliJ 中打开 POM.xml 并执行 Maven 编译或 Maven 包时，它会失败并出现如下错误：

2,27] package org.apache.hadoop.fs does not exist                   
3,27] package org.apache.hadoop.io does not exist                   
4,27] package org.apache.hadoop.io does not exist                   
5,34] package org.apache.hadoop.mapreduce does not exist            
6,44] package org.apache.hadoop.mapreduce.lib.input does not exist  
7,45] package org.apache.hadoop.mapreduce.lib.output does not exist 
:[6,27] package org.apache.hadoop.io does not exist                 
:[7,27] package org.apache.hadoop.io does not exist                 
:[8,31] package org.apache.hadoop.mapred does not exist             
:[9,31] package org.apache.hadoop.mapred does not exist   

还有很多类似这样的符号未找到错误：

[ERROR] /Users/me/Downloads/hadoop-book-master/ch02/src/main/java/oldapi/MaxTemperatureReducer.java:[14,13] cannot find symbol
symbol: class Reducer
  implements Reducer<Text, IntWritable, Text, IntWritable> {
[ERROR] /Users/me/Downloads/hadoop-book-master/ch02/src/main/java/oldapi/MaxTemperatureReducer.java:[14,21] cannot find symbol
symbol: class Text
  implements Reducer<Text, IntWritable, Text, IntWritable> {
[ERROR] /Users/me/Downloads/hadoop-book-master/ch02/src/main/java/oldapi/MaxTemperatureReducer.java:[14,27] cannot find symbol

但是如果我去命令行并复制粘贴他在他的 github 的自述文件中所说的命令，Maven 包就会成功完成。

Then you can build the code with:

% mvn package -DskipTests -Dhadoop.version=1.1.1

(Note that only the Hadoop version numbers specified in hadoop-meta/pom.xml
can be used here, not any version of Hadoop.)