In this paper we examine the possibility of applying Java in the field of telecommunications. We present a method based on formal descriptions we worked out for implementation of communication protocols in Java. We demonstrate how SDL descriptions can be mapped to Java code. We bring out the code of some SDL/PR constructions common for every implementation and parts of SDL descriptions that are implementation specific and apply predefined code patterns. We touch on the problem of mapping abstract data types. This conception is presented by the example of sample telecom protocol INRES and possible connections to the environment are introduced. Then we raise and discuss the matter of automatic compilation and present an SDL/PR to Java compiler. We appraise efficiency of this compilation method and the performance of the realized system. Finally we talk over the advantages and drawbacks of applying Java and give some possible fields of applications.