--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/common/core/src/main/java/com/redhat/thermostat/common/cli/DirectoryContentsCompletionFinder.java	Mon May 30 11:22:19 2016 -0400
@@ -0,0 +1,180 @@
+/*
+ * Copyright 2012-2016 Red Hat, Inc.
+ *
+ * This file is part of Thermostat.
+ *
+ * Thermostat is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published
+ * by the Free Software Foundation; either version 2, or (at your
+ * option) any later version.
+ *
+ * Thermostat is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Thermostat; see the file COPYING.  If not see
+ * <http://www.gnu.org/licenses/>.
+ *
+ * Linking this code with other modules is making a combined work
+ * based on this code.  Thus, the terms and conditions of the GNU
+ * General Public License cover the whole combination.
+ *
+ * As a special exception, the copyright holders of this code give
+ * you permission to link this code with independent modules to
+ * produce an executable, regardless of the license terms of these
+ * independent modules, and to copy and distribute the resulting
+ * executable under terms of your choice, provided that you also
+ * meet, for each linked independent module, the terms and conditions
+ * of the license of that module.  An independent module is a module
+ * which is not derived from or based on this code.  If you modify
+ * this code, you may extend this exception to your version of the
+ * library, but you are not obligated to do so.  If you do not wish
+ * to do so, delete this exception statement from your version.
+ */
+
+package com.redhat.thermostat.common.cli;
+
+import java.io.File;
+import java.io.FileFilter;
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+import java.util.Objects;
+
+/**
+ * A CompletionFinder which provides completions for paths within a specific directory.
+ *
+ * This may be useful for commands which require a path to a config file, which is only
+ * expected to reside within an application-specific directory.
+ *
+ * This is NOT recursive - paths will only be completed if they are direct children of
+ * the specified directory.
+ */
+public class DirectoryContentsCompletionFinder implements CompletionFinder {
+
+    public static final CompletionMode DEFAULT_COMPLETION_MODE = CompletionMode.NAME_ONLY;
+    public static final DefaultFileFilter DEFAULT_FILE_FILTER = new DefaultFileFilter();
+
+    private final File directory;
+    private CompletionMode mode = DEFAULT_COMPLETION_MODE;
+    private FileFilter filter = DEFAULT_FILE_FILTER;
+
+    /**
+     * @param directory the directory to search. Must not be null.
+     */
+    public DirectoryContentsCompletionFinder(File directory) {
+        this.directory = Objects.requireNonNull(directory);
+    }
+
+    /**
+     * Set the configurable completion mode.
+     * The provided completions may be only the file name, or the relative path,
+     * or the absolute path, or the canonical path. This affects what text is
+     * offered as tab completions, but does not affect the search behaviour of
+     * this CompletionFinder.
+     * The default mode is NAME_ONLY.
+     * @param mode the completion mode. Must not be null.
+     */
+    public void setCompletionMode(CompletionMode mode) {
+        this.mode = Objects.requireNonNull(mode);
+    }
+
+    /**
+     * Set the file filter.
+     * This can be used to only suggest completion of files within the specified
+     * directory which also match some criteria. For example, a filter
+     * might be provided which accepts only PNG files, in which case no tab
+     * completions will be offered for JPEGs within the directory. Or for another
+     * example, a filter can even be provided which accepts only subdirectories,
+     * rather than files.
+     * The default filter accepts all files and ignores subdirectories.
+     * @param filter the file filter. Must not be null.
+     */
+    public void setFileFilter(FileFilter filter) {
+        this.filter = Objects.requireNonNull(filter);
+    }
+
+    @Override
+    public List<CompletionInfo> findCompletions() {
+        if (!directory.exists()) {
+            return Collections.emptyList();
+        }
+        if (!directory.canRead()) {
+            return Collections.emptyList();
+        }
+        if (directory.isFile()) {
+            try {
+                return Collections.singletonList(getInfo(directory));
+            } catch (IOException e) {
+                // just ignore this file path
+            }
+        }
+        // path exists, is readable, and is not a file (-> is a directory)
+        List<CompletionInfo> results = new ArrayList<>();
+        for (File file : directory.listFiles(filter)) {
+            try {
+                results.add(getInfo(file));
+            } catch (IOException e) {
+                // just ignore this file path
+            }
+        }
+        return results;
+    }
+
+    private CompletionInfo getInfo(File file) throws IOException {
+        return mode.map(file);
+    }
+
+    public enum CompletionMode {
+        NAME_ONLY(new FileInfoMapper() {
+            @Override
+            public CompletionInfo map(File file) {
+                return new CompletionInfo(file.getName());
+            }
+        }),
+        RELATIVE_PATH(new FileInfoMapper() {
+            @Override
+            public CompletionInfo map(File file) {
+                return new CompletionInfo(file.getPath());
+            }
+        }),
+        ABSOLUTE_PATH(new FileInfoMapper() {
+            @Override
+            public CompletionInfo map(File file) {
+                return new CompletionInfo(file.getAbsolutePath());
+            }
+        }),
+        CANONICAL_PATH(new FileInfoMapper() {
+            @Override
+            public CompletionInfo map(File file) throws IOException {
+                return new CompletionInfo(file.getCanonicalPath());
+            }
+        });
+
+        CompletionMode(FileInfoMapper mapper) {
+            this.mapper = mapper;
+        }
+
+        private FileInfoMapper mapper;
+
+        CompletionInfo map(File file) throws IOException {
+            return mapper.map(file);
+        }
+
+    }
+
+    private interface FileInfoMapper {
+        CompletionInfo map(File file) throws IOException;
+    }
+
+    private static class DefaultFileFilter implements FileFilter {
+        @Override
+        public boolean accept(File file) {
+            return file.isFile();
+        }
+    }
+
+}

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/common/core/src/test/java/com/redhat/thermostat/common/cli/DirectoryContentsCompletionFinderTest.java	Mon May 30 11:22:19 2016 -0400
@@ -0,0 +1,202 @@
+/*
+ * Copyright 2012-2016 Red Hat, Inc.
+ *
+ * This file is part of Thermostat.
+ *
+ * Thermostat is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published
+ * by the Free Software Foundation; either version 2, or (at your
+ * option) any later version.
+ *
+ * Thermostat is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Thermostat; see the file COPYING.  If not see
+ * <http://www.gnu.org/licenses/>.
+ *
+ * Linking this code with other modules is making a combined work
+ * based on this code.  Thus, the terms and conditions of the GNU
+ * General Public License cover the whole combination.
+ *
+ * As a special exception, the copyright holders of this code give
+ * you permission to link this code with independent modules to
+ * produce an executable, regardless of the license terms of these
+ * independent modules, and to copy and distribute the resulting
+ * executable under terms of your choice, provided that you also
+ * meet, for each linked independent module, the terms and conditions
+ * of the license of that module.  An independent module is a module
+ * which is not derived from or based on this code.  If you modify
+ * this code, you may extend this exception to your version of the
+ * library, but you are not obligated to do so.  If you do not wish
+ * to do so, delete this exception statement from your version.
+ */
+
+package com.redhat.thermostat.common.cli;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.mockito.invocation.InvocationOnMock;
+import org.mockito.stubbing.Answer;
+
+import java.io.File;
+import java.io.FileFilter;
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.List;
+
+import static org.hamcrest.CoreMatchers.equalTo;
+import static org.hamcrest.CoreMatchers.is;
+import static org.junit.Assert.assertThat;
+import static org.mockito.Matchers.isA;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.when;
+
+public class DirectoryContentsCompletionFinderTest {
+
+    private File f1;
+    private File f2;
+    private File d1;
+    private File dir;
+    private DirectoryContentsCompletionFinder finder;
+
+    @Before
+    public void setup() throws IOException {
+        f1 = mock(File.class);
+        when(f1.isFile()).thenReturn(true);
+        when(f1.isDirectory()).thenReturn(false);
+        when(f1.getName()).thenReturn("f1");
+        when(f1.getPath()).thenReturn("dir/f1");
+        when(f1.getAbsolutePath()).thenReturn("/some/dir/f1");
+        when(f1.getCanonicalPath()).thenReturn("/some/dir/f1");
+        f2 = mock(File.class);
+        when(f2.isFile()).thenReturn(true);
+        when(f2.isDirectory()).thenReturn(false);
+        when(f2.getName()).thenReturn("f2");
+        when(f2.getPath()).thenReturn("dir/f2");
+        when(f2.getAbsolutePath()).thenReturn("/some/dir/f2");
+        when(f2.getCanonicalPath()).thenReturn("/some/dir/f2");
+        d1 = mock(File.class);
+        when(d1.isFile()).thenReturn(false);
+        when(d1.isDirectory()).thenReturn(true);
+        when(d1.getName()).thenReturn("d1/");
+        when(d1.getPath()).thenReturn("dir/d1/");
+        when(d1.getAbsolutePath()).thenReturn("/some/dir/d1/");
+        when(d1.getCanonicalPath()).thenReturn("/some/dir/d1/");
+        dir = mock(File.class);
+        when(dir.isFile()).thenReturn(false);
+        when(dir.isDirectory()).thenReturn(true);
+        when(dir.exists()).thenReturn(true);
+        when(dir.canRead()).thenReturn(true);
+        when(dir.getName()).thenReturn("dir/");
+        when(dir.getPath()).thenReturn("some/dir/");
+        when(dir.getAbsolutePath()).thenReturn("/some/dir/");
+        when(dir.getCanonicalPath()).thenReturn("/some/dir/");
+        when(dir.list()).thenReturn(new String[]{"f1", "f2", "d1/"});
+        when(dir.listFiles()).thenReturn(new File[]{f1, f2, d1});
+        when(dir.listFiles(isA(FileFilter.class))).thenAnswer(new Answer<File[]>() {
+            @Override
+            public File[] answer(InvocationOnMock invocationOnMock) throws Throwable {
+                List<File> result = new ArrayList<>();
+                FileFilter filter = (FileFilter) invocationOnMock.getArguments()[0];
+                for (File file : dir.listFiles()) {
+                    if (filter.accept(file)) {
+                        result.add(file);
+                    }
+                }
+                return result.toArray(new File[result.size()]);
+            }
+        });
+        finder = new DirectoryContentsCompletionFinder(dir);
+    }
+
+    @Test(expected = NullPointerException.class)
+    public void testDoesNotAcceptNullDirectory() {
+        new DirectoryContentsCompletionFinder(null);
+    }
+
+    @Test(expected = NullPointerException.class)
+    public void testDoesNotAcceptNullMode() {
+        finder.setCompletionMode(null);
+    }
+
+    @Test(expected = NullPointerException.class)
+    public void testDoesNotAcceptNullFilter() {
+        finder.setFileFilter(null);
+    }
+
+    @Test
+    public void testReturnsEmptyIfDirectoryDoesntExist() {
+        when(dir.exists()).thenReturn(false);
+        List<CompletionInfo> list = finder.findCompletions();
+        assertThat(list, is(equalTo(Collections.<CompletionInfo>emptyList())));
+    }
+
+    @Test
+    public void testReturnsEmptyWhenDirectoryExistsButIsNotReadable() {
+        when(dir.exists()).thenReturn(true);
+        when(dir.canRead()).thenReturn(false);
+        List<CompletionInfo> list = finder.findCompletions();
+        assertThat(list, is(equalTo(Collections.<CompletionInfo>emptyList())));
+    }
+
+    @Test
+    public void testReturnsSingleResultWhenDirIsReallyFile() {
+        when(dir.exists()).thenReturn(true);
+        when(dir.canRead()).thenReturn(true);
+        when(dir.isDirectory()).thenReturn(false);
+        when(dir.isFile()).thenReturn(true);
+        List<CompletionInfo> list = finder.findCompletions();
+        assertThat(list.size(), is(1));
+        CompletionInfo info = list.get(0);
+        assertThat(info, is(equalTo(new CompletionInfo(dir.getName()))));
+    }
+
+    @Test
+    public void testFindsOnlyFilesByDefault() {
+        List<CompletionInfo> list = finder.findCompletions();
+        assertThat(list, is(equalTo(Arrays.asList(new CompletionInfo(f1.getName()), new CompletionInfo(f2.getName())))));
+    }
+
+    @Test
+    public void testSetFileFilterWorks() {
+        FileFilter dirFilter = new FileFilter() {
+            @Override
+            public boolean accept(File file) {
+                return file.isDirectory();
+            }
+        };
+        finder.setFileFilter(dirFilter);
+        List<CompletionInfo> list = finder.findCompletions();
+        assertThat(list, is(equalTo(Collections.singletonList(new CompletionInfo(d1.getName())))));
+    }
+
+    @Test
+    public void testRelativePathMode() {
+        finder.setCompletionMode(DirectoryContentsCompletionFinder.CompletionMode.RELATIVE_PATH);
+        List<CompletionInfo> list = finder.findCompletions();
+        assertThat(list,
+                is(equalTo(Arrays.asList(new CompletionInfo(f1.getPath()), new CompletionInfo(f2.getPath())))));
+    }
+
+    @Test
+    public void testAbsolutePathMode() {
+        finder.setCompletionMode(DirectoryContentsCompletionFinder.CompletionMode.ABSOLUTE_PATH);
+        List<CompletionInfo> list = finder.findCompletions();
+        assertThat(list,
+                is(equalTo(Arrays.asList(new CompletionInfo(f1.getAbsolutePath()), new CompletionInfo(f2.getAbsolutePath())))));
+    }
+
+    @Test
+    public void testCanonicalPathMode() throws IOException {
+        finder.setCompletionMode(DirectoryContentsCompletionFinder.CompletionMode.CANONICAL_PATH);
+        List<CompletionInfo> list = finder.findCompletions();
+        assertThat(list,
+                is(equalTo(Arrays.asList(new CompletionInfo(f1.getCanonicalPath()), new CompletionInfo(f2.getCanonicalPath())))));
+    }
+
+}