cassandra_stress Benchmark fails on staticVM's due to Java Issue

Hi ,
I am running the Cassandra on Local Static VM's.
Here is the command and YAML File defined.
python pkb.py --benchmarks=cassandra_stress --benchmark_config_file=/root/Git_Perfkit/cassandra_stress-bare-metal.yaml

YAML:
static_vms:
- &vm0
ip_address: 10.X.X.21
os_type: centos7
user_name: pkb
ssh_private_key: ~/.ssh/id_rsa
internal_ip: 10.X.X.21
disk_specs:
- mount_point: /home
- &vm1
os_type: centos7
ip_address: 10.X.X.20
user_name: pkb
ssh_private_key: ~/.ssh/id_rsa
internal_ip: 10.X.X.20

cassandra_stress:
vm_groups:
workers:
static_vms:
- *vm0
vm_count: 1
client:
static_vms:
- *vm1

flags:
cassandra_concurrent_reads: 32

**Java Error, I am receiving -** Here attached is the log file for your reference

2019-05-27 03:23:49,255 d31ac05a Thread-31 cassandra_stress(1/1) INFO Ran: {ssh -A -p 22 pkb@10.20.7.21 -2 -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no -o IdentitiesOnly=yes -o PreferredAuthentications=publickey -o PasswordAuthentication=no -o ConnectTimeout=5 -o GSSAPIAuthentication=no -o ServerAliveInterval=30 -o ServerAliveCountMax=10 -i ~/.ssh/id_rsa -o ControlPath="/tmp/perfkitbenchmarker/runs/d31ac05a/ssh/%C" -o ControlMaster=auto -o ControlPersist=30m cd /opt/pkb; git clone https://github.com/apache/cassandra.git; cd /opt/pkb/cassandra; git checkout cassandra-2.1.10; /opt/pkb/ant/bin/ant} ReturnCode:1
STDOUT: Cloning into 'cassandra'...
Error: JAVA_HOME is not defined correctly.
We cannot execute /opt/pkb/jdk//bin/java

STDERR: Note: checking out 'cassandra-2.1.10'.

You are in 'detached HEAD' state. You can look around, make experimental
changes and commit them, and you can discard any commits you make in this
state without impacting any branches by performing another checkout.

If you want to create a new branch to retain commits you create, you may
do so (now or later) by using -b with the checkout command again. Example:

git checkout -b new_branch_name

HEAD is now at 78f2e7a... bump version

2019-05-27 03:23:49,264 d31ac05a MainThread cassandra_stress(1/1) ERROR Exception occurred while calling (10.20.7.21):
Traceback (most recent call last):
File "/root/Git_Perfkit/PerfKitBenchmarker/perfkitbenchmarker/background_tasks.py", line 255, in Run
self.return_value = self.target(*self.args, **self.kwargs)
File "/root/Git_Perfkit/PerfKitBenchmarker/perfkitbenchmarker/linux_benchmarks/cassandra_stress_benchmark.py", line 321, in
vm_util.RunThreaded(lambda vm: vm.Install('cassandra'), cassandra_vms)
File "/root/Git_Perfkit/PerfKitBenchmarker/perfkitbenchmarker/linux_virtual_machine.py", line 1104, in Install
package.YumInstall(self)
File "/root/Git_Perfkit/PerfKitBenchmarker/perfkitbenchmarker/linux_packages/cassandra.py", line 93, in YumInstall
_Install(vm)
File "/root/Git_Perfkit/PerfKitBenchmarker/perfkitbenchmarker/linux_packages/cassandra.py", line 84, in _Install
ANT_HOME_DIR))
File "/root/Git_Perfkit/PerfKitBenchmarker/perfkitbenchmarker/linux_virtual_machine.py", line 635, in RemoteCommand
return self.RemoteCommandWithReturnCode(*args, **kwargs)[:2]
File "/root/Git_Perfkit/PerfKitBenchmarker/perfkitbenchmarker/linux_virtual_machine.py", line 651, in RemoteCommandWithReturnCode
return self.RemoteHostCommandWithReturnCode(*args, **kwargs)
File "/root/Git_Perfkit/PerfKitBenchmarker/perfkitbenchmarker/linux_virtual_machine.py", line 721, in RemoteHostCommandWithReturnCode
raise errors.VirtualMachine.RemoteCommandError(error_text)
RemoteCommandError: Got non-zero return code (1) executing cd /opt/pkb; git clone https://github.com/apache/cassandra.git; cd /opt/pkb/cassandra; git checkout cassandra-2.1.10; /opt/pkb/ant/bin/ant
Full command: ssh -A -p 22 pkb@10.20.7.21 -2 -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no -o IdentitiesOnly=yes -o PreferredAuthentications=publickey -o PasswordAuthentication=no -o ConnectTimeout=5 -o GSSAPIAuthentication=no -o ServerAliveInterval=30 -o ServerAliveCountMax=10 -i ~/.ssh/id_rsa -o ControlPath="/tmp/perfkitbenchmarker/runs/d31ac05a/ssh/%C" -o ControlMaster=auto -o ControlPersist=30m cd /opt/pkb; git clone https://github.com/apache/cassandra.git; cd /opt/pkb/cassandra; git checkout cassandra-2.1.10; /opt/pkb/ant/bin/ant
STDOUT: Cloning into 'cassandra'...
Error: JAVA_HOME is not defined correctly.
We cannot execute /opt/pkb/jdk//bin/java
STDERR: Note: checking out 'cassandra-2.1.10'.
[pkb.log](https://github.com/GoogleCloudPlatform/PerfKitBenchmarker/files/3223189/pkb.log)