Add ConsolePasswordFinder to read from Console

build.gradle

@@ -36,7 +36,7 @@ dependencies {
 
   testCompile "junit:junit:4.11"
   testCompile 'org.spockframework:spock-core:1.0-groovy-2.4'
-  testCompile "org.mockito:mockito-core:1.9.5"
+  testCompile "org.mockito:mockito-core:2.8.47"
   testCompile "org.apache.sshd:sshd-core:1.2.0"
   testRuntime "ch.qos.logback:logback-classic:1.1.2"
   testCompile 'org.glassfish.grizzly:grizzly-http-server:2.3.17'

src/main/java/net/schmizz/sshj/userauth/password/ConsolePasswordFinder.java

@@ -0,0 +1,71 @@
+/*
+ * Copyright (C)2009 - SSHJ Contributors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package net.schmizz.sshj.userauth.password;
+
+import java.io.Console;
+import java.util.IllegalFormatException;
+
+/** A PasswordFinder that reads a password from a console */
+public class ConsolePasswordFinder implements PasswordFinder {
+
+    public static final String DEFAULT_FORMAT = "Enter passphrase for %s:";
+
+    private final Console console;
+    private final String promptFormat;
+    private final int maxTries;
+
+    private int numTries;
+
+    public ConsolePasswordFinder() {
+        this(System.console());
+    }
+
+    public ConsolePasswordFinder(Console console) {
+        this(console, DEFAULT_FORMAT, 3);
+    }
+
+    public ConsolePasswordFinder(Console console, String promptFormat, int maxTries) {
+        checkFormatString(promptFormat);
+        this.console = console;
+        this.promptFormat = promptFormat;
+        this.maxTries = maxTries;
+        this.numTries = 0;
+    }
+
+    @Override
+    public char[] reqPassword(Resource<?> resource) {
+        numTries++;
+        if (console == null) {
+            // the request cannot be serviced
+            return null;
+        }
+        return console.readPassword(promptFormat, resource.toString());
+    }
+
+    @Override
+    public boolean shouldRetry(Resource<?> resource) {
+        return numTries < maxTries;
+    }
+
+    private static void checkFormatString(String promptFormat) {
+        try {
+            String.format(promptFormat, "");
+        } catch (IllegalFormatException e) {
+            throw new IllegalArgumentException("promptFormat must have no more than one %s and no other markers", e);
+        }
+    }
+
+}

src/test/java/net/schmizz/sshj/userauth/password/TestConsolePasswordFinder.java

@@ -0,0 +1,83 @@
+/*
+ * Copyright (C)2009 - SSHJ Contributors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package net.schmizz.sshj.userauth.password;
+
+import org.junit.Assert;
+import org.junit.Test;
+import org.mockito.Mockito;
+
+import java.io.Console;
+
+public class TestConsolePasswordFinder {
+
+    private static final String FORMAT = "%s";
+
+    @Test
+    public void testReqPassword() {
+        char[] expectedPassword = "password".toCharArray();
+
+        Console console = Mockito.mock(Console.class);
+        Mockito.when(console.readPassword(Mockito.anyString(), Mockito.any()))
+                .thenReturn(expectedPassword);
+
+        Resource resource = Mockito.mock(Resource.class);
+        char[] password = new ConsolePasswordFinder(console).reqPassword(resource);
+
+        Assert.assertArrayEquals("Password should match mocked return value",
+                expectedPassword, password);
+        Mockito.verifyNoMoreInteractions(resource);
+    }
+
+    @Test
+    public void testReqPasswordNullConsole() {
+        Resource<?> resource = Mockito.mock(Resource.class);
+        char[] password = new ConsolePasswordFinder(null, FORMAT, 1).reqPassword(resource);
+
+        Assert.assertNull("Password should be null with null console", password);
+        Mockito.verifyNoMoreInteractions(resource);
+    }
+
+    @Test
+    public void testShouldRetry() {
+        Resource<String> resource = new PrivateKeyStringResource("");
+        ConsolePasswordFinder finder = new ConsolePasswordFinder(null, FORMAT, 1);
+        Assert.assertTrue("Should allow a retry at first", finder.shouldRetry(resource));
+
+        finder.reqPassword(resource);
+        Assert.assertFalse("Should stop allowing retries after one interaction", finder.shouldRetry(resource));
+    }
+
+    @Test
+    public void testPromptFormat() {
+        Assert.assertNotNull(
+                "Empty format should create valid ConsolePasswordFinder",
+                new ConsolePasswordFinder(null, "", 1));
+        Assert.assertNotNull(
+                "Single-string format should create valid ConsolePasswordFinder",
+                new ConsolePasswordFinder(null, FORMAT, 1));
+    }
+
+    @Test(expected = IllegalArgumentException.class)
+    public void testPromptFormatTooManyMarkers() {
+        new ConsolePasswordFinder(null, "%s%s", 1);
+    }
+
+    @Test(expected = IllegalArgumentException.class)
+    public void testPromptFormatWrongMarkerType() {
+        new ConsolePasswordFinder(null, "%d", 1);
+    }
+
+}

src/test/resources/mockito-extensions/org.mockito.plugins.MockMaker

@@ -0,0 +1,2 @@
+# incubating feature to allow mocking final classes
+mock-maker-inline