Added a class Main

.gitignore

@@ -0,0 +1,3 @@
+.idea
+target
+*.iml

pom.xml

@@ -4,7 +4,34 @@
 
   <groupId>org.mindrot</groupId>
   <artifactId>jbcrypt</artifactId>
-  <version>0.3</version>
+  <version>0.3.1</version>
+
+  <build>
+    <plugins>
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-compiler-plugin</artifactId>
+        <version>2.3.2</version>
+        <configuration>
+          <source>1.6</source>
+          <target>1.6</target>
+        </configuration>
+      </plugin>
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-jar-plugin</artifactId>
+        <version>2.3.2</version>
+        <configuration>
+          <archive>
+            <manifest>
+              <mainClass>Main</mainClass>
+              <packageName></packageName>
+            </manifest>
+          </archive>
+        </configuration>
+      </plugin>
+    </plugins>
+  </build>
   <packaging>jar</packaging>
 
   <name>jbcrypt</name>

src/main/java/Main.java

@@ -0,0 +1,33 @@
+import org.mindrot.*;
+
+public class Main {
+
+  static MainUtil MAIN_UTIL = new MainUtil();
+
+  public static void main(String[] args) {
+    String password;
+    String salt;
+
+    if (args.length==0) {
+      System.out.println("Please specify a secret");
+      MAIN_UTIL.exit(1);
+    } else {
+      password = args[0];
+      salt = MAIN_UTIL.genSalt();
+      System.out.println(BCrypt.hashpw(password, salt));
+      MAIN_UTIL.exit(0);
+    }
+  }
+
+}
+
+
+class MainUtil {
+  public void exit(int exitCode) {
+    System.exit(exitCode);
+  }
+
+  public String genSalt() {
+    return BCrypt.gensalt();
+  }
+}

src/test/java/TestMain.java

@@ -0,0 +1,63 @@
+import java.io.*;
+
+import junit.framework.TestCase;
+import org.mindrot.*;
+
+
+public class TestMain extends TestCase {
+  ByteArrayOutputStream stdout = new ByteArrayOutputStream();
+  String fixedSalt = "$2a$10$MkkJUCZctqHDtrcWu0gfOe";
+  StubbedMainUtil stubbedMainUtil = new StubbedMainUtil(fixedSalt);
+
+  @Override
+  public void setUp() throws Exception {
+    Main.MAIN_UTIL = stubbedMainUtil;
+    PrintStream printStream = new PrintStream(stdout);
+    System.setOut(printStream);
+  }
+
+  public void testIfArgEmptyShowInstruction() throws Exception {
+    Main.main(new String[0]);
+    assertEquals("Please specify a secret\n", stdout.toString());
+  }
+
+  public void testIfArgEmptyExitsWithStatusCode1() throws Exception {
+    Main.main(new String[0]);
+    assertEquals(1, stubbedMainUtil.lastExitCode);
+  }
+
+  public void testIfArgsProvidedReturnHashedSecret() throws Exception {
+    String secret = "pa$$w0rd";
+    String expectedHash = BCrypt.hashpw(secret, fixedSalt) + "\n";
+
+    Main.main(new String[]{secret});
+    String calculatedHash = stdout.toString();
+
+    assertEquals(expectedHash, calculatedHash);
+  }
+
+  public void testIfArgsProvidedExitsWithStatusCode0() throws Exception {
+    Main.main(new String[]{"dummy"});
+    assertEquals(0, stubbedMainUtil.lastExitCode);
+  }
+
+  private class StubbedMainUtil extends MainUtil {
+    final String fixedSalt;
+    int lastExitCode = Integer.MAX_VALUE;
+
+    public StubbedMainUtil(String fixedSalt) {
+      super();
+      this.fixedSalt = fixedSalt;
+    }
+
+    @Override
+    public void exit(int exitCode) {
+      lastExitCode = exitCode;
+    }
+
+    @Override
+    public String genSalt() {
+      return fixedSalt;
+    }
+  }
+}