X-Git-Url: https://mograsim.net/gitweb/?a=blobdiff_plain;ds=sidebyside;f=net.mograsim.logic.core%2Fsrc%2Fnet%2Fmograsim%2Flogic%2Fcore%2Ftypes%2FBitVector.java;h=cce83f43330a9231ee8a37f1bbcf301784430fe0;hb=e8e95e2e345f4d9c5927aa78f5c0fb607d352a97;hp=1e87f9a43cba1c5ec9c4d181571843987b0d599b;hpb=07faf07e3acb8b2afdc2bf65a46bc868faaed0f8;p=Mograsim.git

diff --git a/net.mograsim.logic.core/src/net/mograsim/logic/core/types/BitVector.java b/net.mograsim.logic.core/src/net/mograsim/logic/core/types/BitVector.java
index 1e87f9a4..cce83f43 100644
--- a/net.mograsim.logic.core/src/net/mograsim/logic/core/types/BitVector.java
+++ b/net.mograsim.logic.core/src/net/mograsim/logic/core/types/BitVector.java
@@ -13,7 +13,6 @@ import java.util.function.UnaryOperator;
 /**
  * Immutable class representing a {@link Bit}Vector
  *
- *
  * @author Christian Femers
  *
  */
@@ -23,7 +22,10 @@ public final class BitVector implements StrictLogicType<BitVector>, Iterable<Bit
 
 	private BitVector(Bit[] bits)
 	{
-		this.bits = Objects.requireNonNull(bits);
+		this.bits = Objects.requireNonNull(bits); // do this first to "catch" bits==null before the foreach loop
+		for (Bit bit : bits)
+			if (bit == null)
+				throw new NullPointerException();
 	}
 
 	public static BitVector of(Bit... bits)
@@ -41,11 +43,22 @@ public final class BitVector implements StrictLogicType<BitVector>, Iterable<Bit
 		return BitVectorMutator.of(this);
 	}
 
-	public Bit getBit(int bitIndex)
+	/**
+	 * Returns the most significant bit at <code>bitIndex</code>. (leftmost bit of a binary number at the given index)
+	 */
+	public Bit getMSBit(int bitIndex)
 	{
 		return bits[bitIndex];
 	}
 
+	/**
+	 * Returns the least significant bit at <code>bitIndex</code>. (rightmost bit of a binary number at the given index)
+	 */
+	public Bit getLSBit(int bitIndex)
+	{
+		return bits[bits.length - bitIndex - 1];
+	}
+
 	public Bit[] getBits()
 	{
 		return bits.clone();
@@ -140,7 +153,6 @@ public final class BitVector implements StrictLogicType<BitVector>, Iterable<Bit
 	 *
 	 * @author Christian Femers
 	 */
-	@SuppressWarnings("synthetic-access")
 	public static final class BitVectorMutator implements LogicType<BitVectorMutator, BitVector>
 	{
 		private Bit[] bits;
@@ -155,9 +167,16 @@ public final class BitVector implements StrictLogicType<BitVector>, Iterable<Bit
 			return new BitVectorMutator(bv.getBits());
 		}
 
+		/**
+		 * Returns a new mutator of the specified length, <b>with all bits set to <code>null</code></b>. Use with care!
+		 */
+		public static BitVectorMutator ofLength(int length)
+		{
+			return new BitVectorMutator(new Bit[length]);
+		}
+
 		/**
 		 * Returns an empty mutator which has no bits set and will simply copy the values from the first binary operation performed.
-		 * 
 		 */
 		public static BitVectorMutator empty()
 		{
@@ -169,7 +188,7 @@ public final class BitVector implements StrictLogicType<BitVector>, Iterable<Bit
 		 * 
 		 * @throws IllegalStateException if the mutator is (still) empty
 		 */
-		public BitVector get()
+		public BitVector toBitVector()
 		{
 			if (bits == null)
 				throw new IllegalStateException("cannot create a BitVector from an empty mutator");
@@ -215,6 +234,43 @@ public final class BitVector implements StrictLogicType<BitVector>, Iterable<Bit
 			return this;
 		}
 
+		/**
+		 * Set the most significant bit at <code>bitIndex</code>. (leftmost bit of a binary number at the given index)
+		 */
+		public void setMSBit(int bitIndex, Bit bit)
+		{
+			bits[bitIndex] = bit;
+		}
+
+		/**
+		 * Set the least significant bit at <code>bitIndex</code>. (rightmost bit of a binary number at the given index)
+		 */
+		public void setLSBit(int bitIndex, Bit bit)
+		{
+			bits[bits.length - bitIndex - 1] = bit;
+		}
+
+		/**
+		 * Returns the most significant bit at <code>bitIndex</code>. (leftmost bit of a binary number at the given index)
+		 */
+		public Bit getMSBit(int bitIndex)
+		{
+			return bits[bitIndex];
+		}
+
+		/**
+		 * Returns the least significant bit at <code>bitIndex</code>. (rightmost bit of a binary number at the given index)
+		 */
+		public Bit getLSBit(int bitIndex)
+		{
+			return bits[bits.length - bitIndex - 1];
+		}
+
+		public int length()
+		{
+			return bits.length;
+		}
+
 		private void checkCompatibility(BitVector bv)
 		{
 			if (bits != null && bits.length != bv.length())
@@ -263,7 +319,7 @@ public final class BitVector implements StrictLogicType<BitVector>, Iterable<Bit
 	}
 
 	/**
-	 * All {@link Bit}s symbols concatenated together
+	 * All {@link Bit}s symbols concatenated together (MSB first)
 	 * 
 	 * @see #parse(String)
 	 */
@@ -277,7 +333,7 @@ public final class BitVector implements StrictLogicType<BitVector>, Iterable<Bit
 	}
 
 	/**
-	 * Parses a String containing solely {@link Bit} symbols
+	 * Parses a String containing solely {@link Bit} symbols (MSB first)
 	 * 
 	 * @see #toString()
 	 */
@@ -291,6 +347,9 @@ public final class BitVector implements StrictLogicType<BitVector>, Iterable<Bit
 		return new BitVector(values);
 	}
 
+	/**
+	 * Iterate over the {@link Bit}s of the BitVector <b>from MSB to LSB</b> (left to right).
+	 */
 	@Override
 	public Iterator<Bit> iterator()
 	{
@@ -303,7 +362,7 @@ public final class BitVector implements StrictLogicType<BitVector>, Iterable<Bit
 			{
 				if (!hasNext())
 					throw new NoSuchElementException();
-				return getBit(pos++);
+				return getMSBit(pos++);
 			}
 
 			@Override