Fix sonar issues in files:
https://sonar.onap.org/code?id=org.onap.appc%3Aappc&selected=org.onap.appc%3Aappc-dg-common%3Asrc%2Fmain%2Fjava%2Forg%2Fonap%2Fappc%2Fdg%2Fcommon%2Fimpl%2FAbstractResolver.java
https://sonar.onap.org/code?id=org.onap.appc%3Aappc&selected=org.onap.appc%3Aappc-dg-common%3Asrc%2Fmain%2Fjava%2Forg%2Fonap%2Fappc%2Fdg%2Fcommon%2Fimpl%2FAbstractResolverDataReader.java
https://sonar.onap.org/code?id=org.onap.appc%3Aappc&selected=org.onap.appc%3Aappc-dg-common%3Asrc%2Fmain%2Fjava%2Forg%2Fonap%2Fappc%2Fdg%2Fcommon%2Fimpl%2FConstants.java
https://sonar.onap.org/code?id=org.onap.appc%3Aappc&selected=org.onap.appc%3Aappc-dg-common%3Asrc%2Fmain%2Fjava%2Forg%2Fonap%2Fappc%2Fdg%2Fcommon%2Fimpl%2FDCAEReporterPluginImpl.java
https://sonar.onap.org/code?id=org.onap.appc%3Aappc&selected=org.onap.appc%3Aappc-dg-common%3Asrc%2Fmain%2Fjava%2Forg%2Fonap%2Fappc%2Fdg%2Fcommon%2Fimpl%2FDgResolverPluginImpl.java
https://sonar.onap.org/code?id=org.onap.appc%3Aappc&selected=org.onap.appc%3Aappc-dg-common%3Asrc%2Fmain%2Fjava%2Forg%2Fonap%2Fappc%2Fdg%2Fcommon%2Fimpl%2FIntermediateMessageSenderImpl.java
https://sonar.onap.org/code?id=org.onap.appc%3Aappc&selected=org.onap.appc%3Aappc-dg-common%3Asrc%2Fmain%2Fjava%2Forg%2Fonap%2Fappc%2Fdg%2Fcommon%2Fimpl%2FFlowKey.java
https://sonar.onap.org/code?id=org.onap.appc%3Aappc&selected=org.onap.appc%3Aappc-dg-common%3Asrc%2Fmain%2Fjava%2Forg%2Fonap%2Fappc%2Fdg%2Fcommon%2Fimpl%2FJsonDgUtilImpl.java
https://sonar.onap.org/code?id=org.onap.appc%3Aappc&selected=org.onap.appc%3Aappc-dg-common%3Asrc%2Fmain%2Fjava%2Forg%2Fonap%2Fappc%2Fdg%2Fcommon%2Fimpl%2FLegacyUtilImpl.java
https://sonar.onap.org/code?id=org.onap.appc%3Aappc&selected=org.onap.appc%3Aappc-dg-common%3Asrc%2Fmain%2Fjava%2Forg%2Fonap%2Fappc%2Fdg%2Fcommon%2Fimpl%2FOutputMessagePluginImpl.java
https://sonar.onap.org/code?id=org.onap.appc%3Aappc&selected=org.onap.appc%3Aappc-dg-common%3Asrc%2Fmain%2Fjava%2Forg%2Fonap%2Fappc%2Fdg%2Fcommon%2Fimpl%2FResolverDataReaderFactory.java
https://sonar.onap.org/code?id=org.onap.appc%3Aappc&selected=org.onap.appc%3Aappc-dg-common%3Asrc%2Fmain%2Fjava%2Forg%2Fonap%2Fappc%2Fdg%2Fcommon%2Fimpl%2FVNFCResolver.java
https://sonar.onap.org/code?id=org.onap.appc%3Aappc&selected=org.onap.appc%3Aappc-dg-common%3Asrc%2Fmain%2Fjava%2Forg%2Fonap%2Fappc%2Fdg%2Fcommon%2Fimpl%2FVNFResolver.java
https://sonar.onap.org/code?id=org.onap.appc%3Aappc&selected=org.onap.appc%3Aappc-dg-common%3Asrc%2Fmain%2Fjava%2Forg%2Fonap%2Fappc%2Fdg%2Fcommon%2Fimpl%2FVnfExecutionFlowImpl.java
https://sonar.onap.org/code?id=org.onap.appc%3Aappc&selected=org.onap.appc%3Aappc-dg-common%3Asrc%2Fmain%2Fjava%2Forg%2Fonap%2Fappc%2Fdg%2Fcommon%2Fobjects%2FConnectionDetails.java
https://sonar.onap.org/code?id=org.onap.appc%3Aappc&selected=org.onap.appc%3Aappc-dg-common%3Asrc%2Fmain%2Fjava%2Forg%2Fonap%2Fappc%2Fdg%2Fcommon%2Futils%2FJAXBUtil.java
https://sonar.onap.org/code?id=org.onap.appc%3Aappc&selected=org.onap.appc%3Aappc-dg-common%3Asrc%2Fmain%2Fjava%2Forg%2Fonap%2Fappc%2Fdg%2Fcommon%2Futils%2FJSONUtil.java