Windows 上的 Hadoop - “错误 JAVA_HOME 设置不正确。”

Question

I'm trying to get Hadoop running 'Local Mode' on my Windows machine. I've been using this guide: http://hadoop.apache.org/docs/r1.2.1/single_node_setup.html

When I run the command: bin/hadoop, I get the following error message:

Error: JAVA_HOME is incorrectly set. Please update C:...\\hadoop-2.7.1\\conf\\hadoop-env.cmd

Inside hadoop-env.cmd , I have the line: set JAVA_HOME=%JAVA_HOME%

When I type echo %JAVA_HOME% at the command line I get: C:\\Java\\jdk1.0.8_51

Even if I change the line in hadoop-env.cmd to: set JAVA_HOME=C:\\Java\\jdk1.0.8_51 I get the same error...

How could it be that my JAVA_HOME is incorrectly set?

Answer 1

如果您的JAVA_HOME路径包含空格，则必须使用Windows 8.3路径名

Answer 2

like the other answers, your java environment path must not contain space. The solution is as follows:

1. In the cmd line, charge the directory that contain the jdk (in my case C:\\Program Files\\Java\\jdk1.8.0_73).
2. execute the following line "for %I in (.) do echo %~sI" to display the short name of your installed jdk (in my case C:\\PROGRA~1\\Java\\JDK18~1.0_7)
3. in the file "hadoop-env.cmd", change the line "JAVA_HOME=%JAVA_HOME%" with "JAVA_HOME=C:\\PROGRA~1\\Java\\JDK18~1.0_7".
4. run again the file "hadoop-env.cmd" and it will work correctly.

Answer 3

在conf \\ hadoop-env.cmd中使用“％JAVA_HOME％”

Answer 4

 set JAVA_HOME=C:\Program Files\Java\jdk1.8.0_131\

Above configuration was throwing same error as yours. I updated above with below in hadoop-env.cmd which is infact SFN

set JAVA_HOME=C:\Progra~1\Java\jdk1.8.0_131\

This allowed me to change/have different java version than that of system.

Answer 5

Try removing @ from @rem in hadoop-env.cmd and set JAVA_HOME=%JAVA_HOME%

rem The java implementation to use.  Required.

set JAVA_HOME=%JAVA_HOME%

Then try running hdfs namenode -format

This solution worked for me

Answer 6

if your java environment path contains space, such as "C:\\Program Files\\java\\xxxxx" , the word 《Program Files》 contains a space, so CMD can't identificate

this is the right answer

Answer 7

Try to place the java path in double-coats. Example:

JAVA_HOME="C:\Program Files\Java\jdk-12.0.1"   

It should work fine.

Answer 8

in hadoop-config.xml， the logic is

if not exist %JAVA_HOME%\\bin\\java.exe ( echo Error: JAVA_HOME is incorrectly set. echo Please update %HADOOP_HOME%\\conf\\hadoop-env.cmd goto :eof )

if your java environment path contains space , such as "C:\\Program Files\\java\\xxxxx" , the word 《Program Files》 contains a space , so CMD can't identificate

SO your can change the path instead.