public void execute()

in src/main/org/apache/tools/ant/taskdefs/Tar.java [260:353]
79 lines of code
24 McCabe index (conditional complexity)

    public void execute() throws BuildException {
        if (tarFile == null) {
            throw new BuildException("tarfile attribute must be set!",
                                     getLocation());
        }

        if (tarFile.exists() && tarFile.isDirectory()) {
            throw new BuildException("tarfile is a directory!",
                                     getLocation());
        }

        if (tarFile.exists() && !tarFile.canWrite()) {
            throw new BuildException("Can not write to the specified tarfile!",
                                     getLocation());
        }

        final Vector<TarFileSet> savedFileSets = new Vector<>(filesets);
        try {
            if (baseDir != null) {
                if (!baseDir.exists()) {
                    throw new BuildException("basedir does not exist!",
                                             getLocation());
                }

                // add the main fileset to the list of filesets to process.
                final TarFileSet mainFileSet = new TarFileSet(fileset);
                mainFileSet.setDir(baseDir);
                filesets.addElement(mainFileSet);
            }

            if (filesets.isEmpty() && resourceCollections.isEmpty()) {
                throw new BuildException(
                    "You must supply either a basedir attribute or some nested resource collections.",
                    getLocation());
            }

            // check if tar is out of date with respect to each
            // fileset
            boolean upToDate = true;
            for (final TarFileSet tfs : filesets) {
                upToDate &= check(tfs);
            }
            for (final ResourceCollection rcol : resourceCollections) {
                upToDate &= check(rcol);
            }

            if (upToDate) {
                log("Nothing to do: " + tarFile.getAbsolutePath()
                    + " is up to date.", Project.MSG_INFO);
                return;
            }

            final File parent = tarFile.getParentFile();
            if (parent != null && !parent.isDirectory()
                && !(parent.mkdirs() || parent.isDirectory())) {
                throw new BuildException(
                    "Failed to create missing parent directory for %s",
                    tarFile);
            }

            log("Building tar: " + tarFile.getAbsolutePath(), Project.MSG_INFO);

            try (TarOutputStream tOut = new TarOutputStream(
                compression.compress(new BufferedOutputStream(
                    Files.newOutputStream(tarFile.toPath()))),
                encoding)) {
                tOut.setDebug(true);
                if (longFileMode.isTruncateMode()) {
                    tOut.setLongFileMode(TarOutputStream.LONGFILE_TRUNCATE);
                } else if (longFileMode.isFailMode()
                            || longFileMode.isOmitMode()) {
                    tOut.setLongFileMode(TarOutputStream.LONGFILE_ERROR);
                } else if (longFileMode.isPosixMode()) {
                    tOut.setLongFileMode(TarOutputStream.LONGFILE_POSIX);
                } else {
                    // warn or GNU
                    tOut.setLongFileMode(TarOutputStream.LONGFILE_GNU);
                }

                longWarningGiven = false;
                for (final TarFileSet tfs : filesets) {
                    tar(tfs, tOut);
                }
                for (final ResourceCollection rcol : resourceCollections) {
                    tar(rcol, tOut);
                }
            } catch (final IOException ioe) {
                final String msg = "Problem creating TAR: " + ioe.getMessage();
                throw new BuildException(msg, ioe, getLocation());
            }
        } finally {
            filesets = savedFileSets;
        }
    }