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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def jboss_standalone_conf_file(broker):
 """Get which jboss standalone conf file is using from server log"""

        log_files = broker[JDRSpecs.jboss_standalone_server_log]
        if log_files:
            log_content = log_files[-1].content
            results = []
            for line in log_content:
                if "sun.java.command =" in line and ".jdr" not in line and "-Djboss.server.base.dir" in line:
                    results.append(line)
            if results:
                # default is standalone.xml
                config_xml = 'standalone.xml'
                java_command = results[-1]
                if '--server-config' in java_command:
                    config_xml = java_command.split('--server-config=')[1].split()[0]
                elif '-c ' in java_command:
                    config_xml = java_command.split('-c ')[1].split()[0]
                return [config_xml]
        return []