[HDFS-3482] hdfs balancer throws ArrayIndexOutOfBoundsException if option is specified without arguments

• Type: Bug
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 2.0.0-alpha
• Fix Version/s: 2.6.0
• Component/s: balancer & mover
• Labels: newbie
• Hadoop Flags: Reviewed
• Assignee: madhukara phatak
• Reporter: Stephen Chu
• Created: 31/May/12 16:48
• Updated: 01/Dec/14 03:07
• Resolved: 08/Jul/12 18:40

Description

When running the hdfs balancer with an option but no argument, we run into an ArrayIndexOutOfBoundsException. It's preferable to print the usage.

bash-3.2$ hdfs balancer -threshold
Usage: java Balancer
    [-policy <policy>]	the balancing policy: datanode or blockpool
    [-threshold <threshold>]	Percentage of disk capacity
Balancing took 261.0 milliseconds
12/05/31 09:38:46 ERROR balancer.Balancer: Exiting balancer due an exception
java.lang.ArrayIndexOutOfBoundsException: 1
	at org.apache.hadoop.hdfs.server.balancer.Balancer$Cli.parse(Balancer.java:1505)
	at org.apache.hadoop.hdfs.server.balancer.Balancer$Cli.run(Balancer.java:1482)
	at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:70)
	at org.apache.hadoop.hdfs.server.balancer.Balancer.main(Balancer.java:1555)
bash-3.2$ hdfs balancer -policy
Usage: java Balancer
    [-policy <policy>]	the balancing policy: datanode or blockpool
    [-threshold <threshold>]	Percentage of disk capacity
Balancing took 261.0 milliseconds
12/05/31 09:39:03 ERROR balancer.Balancer: Exiting balancer due an exception
java.lang.ArrayIndexOutOfBoundsException: 1
	at org.apache.hadoop.hdfs.server.balancer.Balancer$Cli.parse(Balancer.java:1520)
	at org.apache.hadoop.hdfs.server.balancer.Balancer$Cli.run(Balancer.java:1482)
	at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:70)
	at org.apache.hadoop.hdfs.server.balancer.Balancer.main(Balancer.java:1555)