The current version of the driver should be compatible with PostgreSQL 8.4 and higher using the version 3.0 of the protocol and Java 8 (JDBC 4.2) or above.
Is an open source JDBC driver written in Pure Java (Type 4), and communicates in the PostgreSQL native network protocol. PostgreSQL JDBC Driver (PgJDBC for short) allows Java programs to connect to a PostgreSQL database using standard, database independent Java code.