Add unit tests for Signing class

All methods that I changed in previous commits of this PR are covered,
and the tests path both before and after my refactorings.

src/test/java/jota/SigningTest.java

@@ -0,0 +1,61 @@
+package jota;
+
+import jota.error.InvalidAddressException;
+import jota.model.Bundle;
+import jota.utils.Checksum;
+import jota.utils.Constants;
+import jota.utils.Converter;
+import jota.utils.InputValidator;
+import jota.utils.IotaAPIUtils;
+import jota.utils.SeedRandomGenerator;
+import jota.utils.Signing;
+
+import org.junit.Test;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+
+import java.util.Arrays;
+
+/**
+ * @author schierlm@gmx.de
+ */
+public class SigningTest {
+
+    private static final String TEST_SEED = "IHDEENZYITYVYSPKAURUZAQKGVJEREFDJMYTANNXXGPZ9GJWTEOJJ9IPMXOGZNQLSNMFDSQOTZAEETUEA";
+    private static final String FIRST_ADDR = "LXQHWNY9CQOHPNMKFJFIJHGEPAENAOVFRDIBF99PPHDTWJDCGHLYETXT9NPUVSNKT9XDTDYNJKJCPQMZCCOZVXMTXC";
+    private static final String SIXTH_ADDR = "HLHRSJNPUUGRYOVYPSTEQJKETXNXDIWQURLTYDBJADGIYZCFXZTTFSOCECPPPPY9BYWPODZOCWJKXEWXDPUYEOTFQA";
+    private static final String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
+    private static final String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
+
+    @Test
+    public void testAddressGeneration() throws InvalidAddressException {
+        assertEquals(FIRST_ADDR, IotaAPIUtils.newAddress(TEST_SEED, 2, 0, true, null));
+        assertEquals(SIXTH_ADDR, IotaAPIUtils.newAddress(TEST_SEED, 2, 5, true, null));
+    }
+
+    @Test
+    public void testSigning() throws InvalidAddressException {
+        // we can sign any hash, so for convenience we will sign the first
+        // address of our test seed
+        // (but remove the checksum) with the key of our fifth address
+        String hashToSign = removeChecksum(FIRST_ADDR);
+        Signing signing = new Signing(null);
+        final int[] key = signing.key(Converter.trits(TEST_SEED), 5, 2);
+        int[] normalizedHash = new Bundle().normalizedBundle(hashToSign);
+        int[] signature = signing.signatureFragment(Arrays.copyOfRange(normalizedHash, 0, 27), Arrays.copyOfRange(key, 0, 6561));
+        assertEquals(SIGNATURE1, Converter.trytes(signature));
+        int[] signature2 = signing.signatureFragment(Arrays.copyOfRange(normalizedHash, 27, 27 * 2), Arrays.copyOfRange(key, 6561, 6561 * 2));
+        assertEquals(SIGNATURE2, Converter.trytes(signature2));
+    }
+
+    @Test
+    public void testVerifying() throws InvalidAddressException {
+        assertTrue(new Signing(null).validateSignatures(removeChecksum(SIXTH_ADDR), new String[] { SIGNATURE1, SIGNATURE2 }, removeChecksum(FIRST_ADDR)));
+    }
+
+    private String removeChecksum(String address) throws InvalidAddressException {
+        assertTrue(Checksum.isValidChecksum(address));
+        return address.substring(0, Constants.ADDRESS_LENGTH_WITHOUT_CHECKSUM);
+    }
+}