Unit testing. MemoryRange work.

src/main/java/com/loomcom/lm6502/MemoryRange.java

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+package com.loomcom.lm6502;
+
+public class MemoryRange implements Comparable<MemoryRange> {
+	public int startAddress;
+	public int endAddress;
+
+	public MemoryRange(int startAddress, int endAddress)
+		    throws MemoryRangeException {
+		if (startAddress < 0 || endAddress < 0) {
+			throw new MemoryRangeException("Addresses cannot be less than 0.");
+		}
+		if (startAddress >= endAddress) {
+			throw new MemoryRangeException("End address must be greater than start address.");
+		}
+		this.startAddress = startAddress;
+		this.endAddress = endAddress;
+	}
+
+	public int getStartAddress() {
+		return startAddress;
+	}
+
+	public int getEndAddress() {
+		return endAddress;
+	}
+
+	/**
+	 * Checks for address inclusion in the range.
+	 *
+	 * @returns true if the address is included within this range,
+	 *					false otherwise.
+	 */
+	public boolean includes(int address) {
+		return (address <= endAddress &&
+		        address >= startAddress);
+	}
+
+	/**
+	 * Checks for overlapping memory ranges.
+	 *
+	 * @returns true if this range overlaps in any way with the other.
+	 */
+	public boolean overlapsWith(MemoryRange other) {
+		return ((this.getEndAddress() >= other.getStartAddress() &&
+						 this.getEndAddress() <= other.getEndAddress()) ||
+						(other.getEndAddress() >= this.getStartAddress() &&
+						 other.getEndAddress() <= this.getEndAddress()) ||
+						(this.getStartAddress() <= other.getStartAddress() &&
+						 this.getEndAddress() >= other.getEndAddress()) ||
+						(other.getStartAddress() <= this.getStartAddress() &&
+						 other.getEndAddress() >= this.getEndAddress()));
+	}
+
+	// Implementation of Comparable interface
+	public int compareTo(MemoryRange other) {
+		if (other == null) {
+			throw new NullPointerException("Cannot compare to null.");
+		}
+		if (this == other) {
+			return 0;
+		}
+		Integer thisStartAddr = new Integer(this.getStartAddress());
+		Integer thatStartAddr = new Integer(other.getStartAddress());
+		return thisStartAddr.compareTo(thatStartAddr);
+	}
+}