public static boolean isOs()

in src/main/org/apache/tools/ant/taskdefs/condition/Os.java [246:335]
81 lines of code
37 McCabe index (conditional complexity)

    public static boolean isOs(String family, String name, String arch,
                               String version) {
        boolean retValue = false;

        if (family != null || name != null || arch != null
            || version != null) {

            boolean isFamily = true;
            boolean isName = true;
            boolean isArch = true;
            boolean isVersion = true;

            if (family != null) {

                //windows probing logic relies on the word 'windows' in
                //the OS
                boolean isWindows = OS_NAME.contains(FAMILY_WINDOWS);
                boolean is9x = false;
                boolean isNT = false;
                if (isWindows) {
                    //there are only four 9x platforms that we look for
                    is9x = (OS_NAME.contains("95")
                            || OS_NAME.contains("98")
                            || OS_NAME.contains("me")
                            //wince isn't really 9x, but crippled enough to
                            //be a muchness. Ant doesn't run on CE, anyway.
                            || OS_NAME.contains("ce"));
                    isNT = !is9x;
                }
                switch (family) {
                    case FAMILY_WINDOWS:
                        isFamily = isWindows;
                        break;
                    case FAMILY_9X:
                        isFamily = isWindows && is9x;
                        break;
                    case FAMILY_NT:
                        isFamily = isWindows && isNT;
                        break;
                    case FAMILY_OS2:
                        isFamily = OS_NAME.contains(FAMILY_OS2);
                        break;
                    case FAMILY_NETWARE:
                        isFamily = OS_NAME.contains(FAMILY_NETWARE);
                        break;
                    case FAMILY_DOS:
                        isFamily = PATH_SEP.equals(";") && !isFamily(FAMILY_NETWARE);
                        break;
                    case FAMILY_MAC:
                        isFamily = OS_NAME.contains(FAMILY_MAC)
                                || OS_NAME.contains(DARWIN);
                        break;
                    case FAMILY_TANDEM:
                        isFamily = OS_NAME.contains("nonstop_kernel");
                        break;
                    case FAMILY_UNIX:
                        isFamily = PATH_SEP.equals(":")
                                && !isFamily(FAMILY_VMS)
                                && (!isFamily(FAMILY_MAC) || OS_NAME.endsWith("x")
                                || OS_NAME.contains(DARWIN));
                        break;
                    case FAMILY_ZOS:
                        isFamily = OS_NAME.contains(FAMILY_ZOS)
                                || OS_NAME.contains("os/390");
                        break;
                    case FAMILY_OS400:
                        isFamily = OS_NAME.contains(FAMILY_OS400);
                        break;
                    case FAMILY_VMS:
                        isFamily = OS_NAME.contains(FAMILY_VMS);
                        break;
                    default:
                        throw new BuildException(
                                "Don't know how to detect os family \""
                                        + family + "\"");
                }
            }
            if (name != null) {
                isName = name.equals(OS_NAME);
            }
            if (arch != null) {
                isArch = arch.equals(OS_ARCH);
            }
            if (version != null) {
                isVersion = version.equals(OS_VERSION);
            }
            retValue = isFamily && isName && isArch && isVersion;
        }
        return retValue;
    }