add method and tests

Add method bytesToStringNoSpace for byte and setBit
devnied · Jul 5, 2014 · fa586da · fa586da
1 parent 36faf29
commit fa586da
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Showing 2 changed files with 98 additions and 3 deletions.
diff --git a/src/main/java/fr/devnied/bitlib/BytesUtils.java b/src/main/java/fr/devnied/bitlib/BytesUtils.java
@@ -58,7 +58,7 @@ public static int byteArrayToInt(final byte[] byteArray) {
 	 *            start position in array in the
 	 * @param length
 	 *            length of data
-	 * @return
+	 * @return int value of byte array
 	 */
 	public static int byteArrayToInt(final byte[] byteArray, final int startPos, final int length) {
 		if (byteArray == null) {
@@ -101,6 +101,17 @@ public static String bytesToString(final byte[] pBytes, final boolean pTruncate)
 		return formatByte(pBytes, FORMAT_SPACE, pTruncate);
 	}
 
+	/**
+	 * Method to convert byte to string without space between byte
+	 * 
+	 * @param pByte
+	 *            byte to convert
+	 * @return a string
+	 */
+	public static String bytesToStringNoSpace(final byte pByte) {
+		return formatByte(new byte[] { pByte }, FORMAT_NOSPACE, false);
+	}
+
 	/**
 	 * Method to convert bytes to string without space between bytes
 	 * 
@@ -177,15 +188,18 @@ public static byte[] fromString(final String pData) {
 	}
 
 	/**
-	 * Test if bit at given index of given value is = 1
+	 * Test if bit at given index of given value is = 1.
 	 * 
 	 * @param pVal
 	 *            value to test
 	 * @param pBitIndex
-	 *            bit index
+	 *            bit index between 0 and 7
 	 * @return true bit at given index of give value is = 1
 	 */
 	public static boolean matchBitByBitIndex(final int pVal, final int pBitIndex) {
+		if (pBitIndex < 0 || pBitIndex > 7) {
+			throw new IllegalArgumentException("parameter 'pBitIndex' must be between 0 and 7. pBitIndex=" + pBitIndex);
+		}
 		return (pVal & 1 << pBitIndex) != 0;
 	}
 
@@ -202,6 +216,30 @@ public static boolean matchBitByValue(final int pInitialValue, final int pValueT
 		return matchBitByBitIndex(pInitialValue, MAX_BIT_INTEGER - Integer.numberOfLeadingZeros(pValueToCompare));
 	}
 
+	/**
+	 * Method used to set a bit index to 1 or 0.
+	 * 
+	 * @param data
+	 *            data to modify
+	 * @param pBitIndex
+	 *            index to set
+	 * @param pOn
+	 *            set bit at specified index to 1 or 0
+	 * @return the modified byte
+	 */
+	public static byte setBit(final byte pData, final int pBitIndex, final boolean pOn) {
+		if (pBitIndex < 0 || pBitIndex > 7) {
+			throw new IllegalArgumentException("parameter 'pBitIndex' must be between 0 and 7. pBitIndex=" + pBitIndex);
+		}
+		byte ret = pData;
+		if (pOn) { // Set bit
+			ret |= 1 << pBitIndex;
+		} else { // Unset bit
+			ret &= ~(1 << pBitIndex);
+		}
+		return ret;
+	}
+
 	/**
 	 * Convert byte array to binary String
 	 * 

diff --git a/src/test/java/fr/devnied/bitlib/BytesUtilsTest.java b/src/test/java/fr/devnied/bitlib/BytesUtilsTest.java
@@ -111,6 +111,16 @@ public void testBytesToStringNoSpace() {
 		Assertions.assertThat(BytesUtils.bytesToStringNoSpace(tab2)).isEqualTo("00010245");
 	}
 
+	/**
+	 * 
+	 */
+	@Test
+	public void testBytesToStringNoSpacebyte() {
+		Assertions.assertThat(BytesUtils.bytesToStringNoSpace((byte) 0)).isEqualTo("00");
+		Assertions.assertThat(BytesUtils.bytesToStringNoSpace((byte) 255)).isEqualTo("FF");
+		Assertions.assertThat(BytesUtils.bytesToStringNoSpace(null)).isEqualTo("");
+	}
+
 	/**
 	 * 
 	 */
@@ -157,6 +167,53 @@ public void testMatchBit() {
 		Assertions.assertThat(BytesUtils.matchBitByValue(10, 1)).isEqualTo(false);
 	}
 
+	/**
+	 * 
+	 */
+	@Test
+	public void testMatchBitByBitIndex() {
+		Assertions.assertThat(BytesUtils.matchBitByBitIndex(1, 0)).isEqualTo(true);
+		Assertions.assertThat(BytesUtils.matchBitByBitIndex(128, 7)).isEqualTo(true);
+		Assertions.assertThat(BytesUtils.matchBitByBitIndex(127, 7)).isEqualTo(false);
+		Assertions.assertThat(BytesUtils.matchBitByBitIndex(255, 7)).isEqualTo(true);
+		Assertions.assertThat(BytesUtils.matchBitByBitIndex(0, 0)).isEqualTo(false);
+
+		try {
+			BytesUtils.matchBitByBitIndex(0, -1);
+			Assert.fail();
+		} catch (Exception e) {
+		}
+		try {
+			BytesUtils.matchBitByBitIndex(0, 8);
+			Assert.fail();
+		} catch (Exception e) {
+		}
+	}
+
+	/**
+	 * 
+	 */
+	@Test
+	public void testSetBytes() {
+		byte max = (byte) 0xFF;
+		byte min = 0;
+		Assertions.assertThat(BytesUtils.bytesToStringNoSpace(BytesUtils.setBit(min, 7, true))).isEqualTo("80");
+		Assertions.assertThat(BytesUtils.bytesToStringNoSpace(BytesUtils.setBit(min, 0, true))).isEqualTo("01");
+		Assertions.assertThat(BytesUtils.bytesToStringNoSpace(BytesUtils.setBit(max, 4, false))).isEqualTo("EF");
+		Assertions.assertThat(BytesUtils.bytesToStringNoSpace(BytesUtils.setBit(max, 0, false))).isEqualTo("FE");
+		Assertions.assertThat(BytesUtils.bytesToStringNoSpace(BytesUtils.setBit(min, 0, false))).isEqualTo("00");
+		try {
+			BytesUtils.setBit(max, -1, false);
+			Assert.fail();
+		} catch (Exception e) {
+		}
+		try {
+			BytesUtils.setBit(max, 8, false);
+			Assert.fail();
+		} catch (Exception e) {
+		}
+	}
+
 	/**
 	 * 
 	 */