InetAddress.getHostName() does not resolve host names, which differs from the Sun's JDK behaviour. Consider the following test case:
import java.net.InetAddress; public class Test { public static void main(String[] argv) throws Exception { String resolved = InetAddress.getByName("127.0.0.1").getHostName(); System.out.println("127.0.0.1 hostname: expected=localhost, actual=" + resolved); } } With Sun's JDK: $ java -version java version "1.4.2_04" Java(TM) 2 Runtime Environment, Standard Edition (build 1.4.2_04-b05) Java HotSpot(TM) Client VM (build 1.4.2_04-b05, mixed mode) $ javac Test.java $ java -cp . Test 127.0.0.1 hostname: expected=localhost, actual=localhost With GCJ 4.2 (snapshot of 20061128): $ gcj -v Using built-in specs. Reading specs from /opt/gcc-4.2/lib/gcc/sparc-sun-solaris2.8/4.2.0/../../../libgcj.spec rename spec startfile to startfileorig rename spec lib to liborig Target: sparc-sun-solaris2.8 Configured with: ../gcc-4.2-20061128/configure --prefix=/opt/gcc-4.2 --disable-nls Thread model: posix gcc version 4.2.0 20061128 (prerelease) $ gcj -L/opt/gcc-4.2/lib -lstdc++ -L/usr/local/lib -o Test --main=Test Test.class $ ./Test 127.0.0.1 hostname: expected=localhost, actual=127.0.0.1 Same results with gcj 4.0.2. -- Summary: InetAddress.getHostName() does not resolve host names Product: gcc Version: 4.2.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: libgcj AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: renaud dot saintgratien at orange-ftgroup dot com GCC host triplet: sparc-sun-solaris2.8 http://gcc.gnu.org/bugzilla/show_bug.cgi?id=30109