[rb] Use Bazel JDK when starting server

This ensures the server is not started with a system JDK which might be
missing, outdated or simply inaccessible due to Bazel test sandboxing.

rb/lib/selenium/server.rb

@@ -241,7 +241,7 @@ def process
         # extract any additional_args that start with -D as options
         properties = @additional_args.dup - @additional_args.delete_if { |arg| arg[/^-D/] }
         args = ['-jar', @jar, @role, '--port', @port.to_s]
-        server_command = ['java'] + properties + args + @additional_args
+        server_command = [java_bin] + properties + args + @additional_args
         cp = WebDriver::ChildProcess.build(*server_command)
 
         if @log.is_a?(String)
@@ -256,6 +256,18 @@ def process
       end
     end
 
+    def java_bin
+      if ENV.key?('BAZEL_TEST') && ENV.key?('JAVA_HOME')
+        if WebDriver::Platform.windows?
+          "#{ENV['JAVA_HOME']}/bin/java.exe"
+        else
+          "#{ENV['JAVA_HOME']}/bin/java"
+        end
+      else
+        'java'
+      end
+    end
+
     def poll_for_service
       return if socket.connected?
 

rb/spec/unit/selenium/server_spec.rb

@@ -48,7 +48,7 @@ module Selenium
     it 'uses the given jar file and port' do
       allow(File).to receive(:exist?).with('selenium_server_deploy.jar').and_return(true)
       allow(WebDriver::ChildProcess).to receive(:build)
-        .with('java', '-jar', 'selenium_server_deploy.jar', 'standalone', '--port', '1234')
+        .with(a_string_ending_with('java'), '-jar', 'selenium_server_deploy.jar', 'standalone', '--port', '1234')
         .and_return(mock_process)
 
       server = described_class.new('selenium_server_deploy.jar', port: 1234, background: true)
@@ -57,13 +57,13 @@ module Selenium
       server.start
       expect(File).to have_received(:exist?).with('selenium_server_deploy.jar')
       expect(WebDriver::ChildProcess).to have_received(:build)
-        .with('java', '-jar', 'selenium_server_deploy.jar', 'standalone', '--port', '1234')
+        .with(a_string_ending_with('java'), '-jar', 'selenium_server_deploy.jar', 'standalone', '--port', '1234')
     end
 
     it 'waits for the server process by default' do
       allow(File).to receive(:exist?).with('selenium_server_deploy.jar').and_return(true)
       allow(WebDriver::ChildProcess).to receive(:build)
-        .with('java', '-jar', 'selenium_server_deploy.jar', 'standalone', '--port', port.to_s)
+        .with(a_string_ending_with('java'), '-jar', 'selenium_server_deploy.jar', 'standalone', '--port', port.to_s)
         .and_return(mock_process)
 
       server = described_class.new('selenium_server_deploy.jar', port: port)
@@ -74,14 +74,14 @@ module Selenium
 
       expect(File).to have_received(:exist?).with('selenium_server_deploy.jar')
       expect(WebDriver::ChildProcess).to have_received(:build)
-        .with('java', '-jar', 'selenium_server_deploy.jar', 'standalone', '--port', port.to_s)
+        .with(a_string_ending_with('java'), '-jar', 'selenium_server_deploy.jar', 'standalone', '--port', port.to_s)
       expect(mock_process).to have_received(:wait)
     end
 
     it 'adds additional args' do
       allow(File).to receive(:exist?).with('selenium_server_deploy.jar').and_return(true)
       allow(WebDriver::ChildProcess).to receive(:build)
-        .with('java', '-jar', 'selenium_server_deploy.jar', 'standalone', '--port', port.to_s, 'foo', 'bar')
+        .with(a_string_ending_with('java'), '-jar', 'selenium_server_deploy.jar', 'standalone', '--port', port.to_s, 'foo', 'bar')
         .and_return(mock_process)
 
       server = described_class.new('selenium_server_deploy.jar', port: port, background: true)
@@ -92,14 +92,14 @@ module Selenium
       server.start
       expect(File).to have_received(:exist?).with('selenium_server_deploy.jar')
       expect(WebDriver::ChildProcess).to have_received(:build)
-        .with('java', '-jar', 'selenium_server_deploy.jar', 'standalone',
+        .with(a_string_ending_with('java'), '-jar', 'selenium_server_deploy.jar', 'standalone',
               '--port', port.to_s, 'foo', 'bar')
     end
 
     it 'adds additional JAVA options args' do
       allow(File).to receive(:exist?).with('selenium_server_deploy.jar').and_return(true)
       allow(WebDriver::ChildProcess).to receive(:build)
-        .with('java',
+        .with(a_string_ending_with('java'),
               '-Dwebdriver.chrome.driver=/bin/chromedriver',
               '-jar', 'selenium_server_deploy.jar',
               'standalone',
@@ -117,7 +117,7 @@ module Selenium
       server.start
       expect(File).to have_received(:exist?).with('selenium_server_deploy.jar')
       expect(WebDriver::ChildProcess).to have_received(:build)
-        .with('java',
+        .with(a_string_ending_with('java'),
               '-Dwebdriver.chrome.driver=/bin/chromedriver',
               '-jar', 'selenium_server_deploy.jar',
               'standalone',
@@ -194,7 +194,7 @@ module Selenium
     it 'raises Selenium::Server::Error if the server is not launched within the timeout' do
       allow(File).to receive(:exist?).with('selenium_server_deploy.jar').and_return(true)
       allow(WebDriver::ChildProcess).to receive(:build)
-        .with('java', '-jar', 'selenium_server_deploy.jar', 'standalone', '--port', port.to_s)
+        .with(a_string_ending_with('java'), '-jar', 'selenium_server_deploy.jar', 'standalone', '--port', port.to_s)
         .and_return(mock_process)
 
       poller = instance_double(WebDriver::SocketPoller)