Address IntelliJ warnings

This commit addresses a large number of IntelliJ warnings
that have been left hanging around for far too long.

src/main/java/com/loomcom/symon/devices/Acia.java

@@ -32,7 +32,7 @@ import com.loomcom.symon.exceptions.MemoryRangeException;
 
 public abstract class Acia extends Device {
 
-    private String name;
+    private final String name;
 
     /**
      * Register addresses

src/main/java/com/loomcom/symon/devices/Acia6551.java

@@ -121,9 +121,6 @@ public class Acia6551 extends Acia {
         // Mask the lower four bits to get the baud rate.
         int baudSelector = data & 0x0f;
         switch (baudSelector) {
-            case 0:
-                rate = 0;
-                break;
             case 1:
                 rate = 50;
                 break;
@@ -169,6 +166,8 @@ public class Acia6551 extends Acia {
             case 15:
                 rate = 19200;
                 break;
+            default:
+                break;
         }
 
         setBaudRate(rate);

src/main/java/com/loomcom/symon/devices/Acia6850.java

@@ -31,7 +31,7 @@ import com.loomcom.symon.exceptions.MemoryRangeException;
 /**
  * This is a simulation of the Motorola 6850 ACIA, with limited
  * functionality.
- *
+ * <p>
  * Unlike a 16550 UART, the 6850 ACIA has only one-byte transmit and
  * receive buffers. It is the programmer's responsibility to check the
  * status (full or empty) for transmit and receive buffers before

src/main/java/com/loomcom/symon/devices/Crtc.java

@@ -26,8 +26,6 @@ package com.loomcom.symon.devices;
 import com.loomcom.symon.exceptions.MemoryAccessException;
 import com.loomcom.symon.exceptions.MemoryRangeException;
 
-import java.io.IOException;
-
 /**
  * Simulation of a 6545 CRTC and virtual CRT output.
  */
@@ -87,9 +85,9 @@ public class Crtc extends Device {
     private boolean displayEnableSkew = false;
     private boolean cursorSkew = false;
 
-    private Memory memory;
+    private final Memory memory;
 
-    public Crtc(int deviceAddress, Memory memory) throws MemoryRangeException, IOException {
+    public Crtc(int deviceAddress, Memory memory) throws MemoryRangeException {
         super(deviceAddress, deviceAddress + 2, "CRTC");
         this.memory = memory;
 
@@ -120,19 +118,17 @@ public class Crtc extends Device {
 
     @Override
     public int read(int address, boolean cpuAccess) throws MemoryAccessException {
-        switch (address) {
-            case REGISTER_RW:
-                switch (currentRegister) {
-                    case CURSOR_POSITION_LOW:
-                        return cursorPosition & 0xff;
-                    case CURSOR_POSITION_HIGH:
-                        return cursorPosition >> 8;
-                    default:
-                        return 0;
-                }
-            default:
-                return 0;
+        if (address == REGISTER_RW) {
+            switch (currentRegister) {
+                case CURSOR_POSITION_LOW:
+                    return cursorPosition & 0xff;
+                case CURSOR_POSITION_HIGH:
+                    return cursorPosition >> 8;
+                default:
+                    return 0;
+            }
         }
+        return 0;
     }
 
     @Override

src/main/java/com/loomcom/symon/devices/Device.java

@@ -45,7 +45,7 @@ public abstract class Device implements Comparable<Device> {
     /**
      * The memory range for this device.
      */
-    private MemoryRange memoryRange;
+    private final MemoryRange memoryRange;
 
     /**
      * The name of the device.
@@ -60,7 +60,7 @@ public abstract class Device implements Comparable<Device> {
     /**
      * Listeners to notify on update.
      */
-    private Set<DeviceChangeListener> deviceChangeListeners;
+    private final Set<DeviceChangeListener> deviceChangeListeners;
 
     public Device(int startAddress, int endAddress, String name) throws MemoryRangeException {
         this.memoryRange = new MemoryRange(startAddress, endAddress);

src/main/java/com/loomcom/symon/devices/Memory.java

@@ -30,8 +30,8 @@ import com.loomcom.symon.exceptions.*;
 
 public class Memory extends Device {
 
-    private boolean readOnly;
-    private int[] mem;
+    private final boolean readOnly;
+    private final int[] mem;
 
     /* Initialize all locations to 0x00 (BRK) */
     private static final int DEFAULT_FILL = 0x00;

src/main/java/com/loomcom/symon/devices/SdController.java

@@ -119,7 +119,10 @@ public class SdController extends Device {
         if (sdImageFile != null) {
             try {
                 FileInputStream fis = new FileInputStream(sdImageFile);
-                fis.skip(this.position);
+                long bytesSkipped = fis.skip(this.position);
+                if (bytesSkipped < this.position) {
+                    logger.log(Level.WARNING, "Failed to seek to position " + this.position);
+                }
                 int read = fis.read(readBuffer);
                 if (read < SECTOR_SIZE) {
                     logger.log(Level.WARNING, "not enough data to fill read buffer from SD image file");

src/main/java/com/loomcom/symon/devices/Via6522.java

@@ -27,83 +27,23 @@ import com.loomcom.symon.exceptions.MemoryAccessException;
 import com.loomcom.symon.exceptions.MemoryRangeException;
 
 /**
- * Very basic implementation of a MOS 6522 VIA.
- *
- * TODO: Implement timers as threads.
+ * Skeleton for future implementation of a MOS 6522 VIA.
  */
 public class Via6522 extends Pia {
     public static final int VIA_SIZE = 16;
 
-    enum Register {
-        ORB, ORA, DDRB, DDRA, T1C_L, T1C_H, T1L_L, T1L_H,
-        T2C_L, T2C_H, SR, ACR, PCR, IFR, IER, ORA_H
-    }
-
     public Via6522(int address) throws MemoryRangeException {
         super(address, address + VIA_SIZE - 1, "MOS 6522 VIA");
     }
 
     @Override
     public void write(int address, int data) throws MemoryAccessException {
-        Register[] registers = Register.values();
-
-        if (address >= registers.length) {
-            throw new MemoryAccessException("Unknown register: " + address);
-        }
-
-        Register r = registers[address];
-
-        switch (r) {
-            case ORA:
-            case ORB:
-            case DDRA:
-            case DDRB:
-            case T1C_L:
-            case T1C_H:
-            case T1L_L:
-            case T1L_H:
-            case T2C_L:
-            case T2C_H:
-            case SR:
-            case ACR:
-            case PCR:
-            case IFR:
-            case IER:
-            case ORA_H:
-            default:
-        }
+        // TODO: Implement write.
     }
 
     @Override
     public int read(int address, boolean cpuAccess) throws MemoryAccessException {
-        Register[] registers = Register.values();
-
-        if (address >= registers.length) {
-            throw new MemoryAccessException("Unknown register: " + address);
-        }
-
-        Register r = registers[address];
-
-        switch (r) {
-            case ORA:
-            case ORB:
-            case DDRA:
-            case DDRB:
-            case T1C_L:
-            case T1C_H:
-            case T1L_L:
-            case T1L_H:
-            case T2C_L:
-            case T2C_H:
-            case SR:
-            case ACR:
-            case PCR:
-            case IFR:
-            case IER:
-            case ORA_H:
-            default:
-        }
-
+        // TODO: Implement read.
         return 0;
     }
 }