Do multiple refactors for better performance/code-style

src/main/java/com/github/khalidzahra/TopologyAPI.java

@@ -52,21 +52,23 @@ public boolean writeJSON(String topologyID, String filePath) {
     /**
      * Queries all topologies currently stored in memory
      *
-     * @return Returns a List of Topology containing all loaded topologies. Returns an empty list if no topologies are found.
+     * @return Returns a List of Topology containing all loaded topologies.
+     * Returns an empty list if no topologies are found.
      */
     public List<Topology> queryTopologies() {
         return topologyRegistry.getTopologyList();
     }
 
     /**
      * Finds topology with specified topology ID
+     *
      * @param topologyID String variable containing the topology ID
      * @return Returns Topology object with specified topology ID
      */
     public Topology findTopology(String topologyID) {
         return topologyRegistry.getTopologyList()
                 .stream()
-                .filter(topology -> topology.getId().equals(topologyID))
+                .filter(topology -> topology.getTopologyId().equals(topologyID))
                 .findAny()
                 .orElse(null);
     }
@@ -85,7 +87,8 @@ public boolean deleteTopology(String topologyID) {
      * Queries the devices connected within a topology
      *
      * @param topologyID String variable containing the topology ID
-     * @return Returns a List of Device containing all connected devices. Returns an empty list if no devices are found.
+     * @return Returns a List of Device containing all connected devices.
+     * Returns an empty list if no devices are found.
      */
     public List<Device> queryDevices(String topologyID) {
         Topology topology = topologyRegistry.findTopology(topologyID);
@@ -97,7 +100,8 @@ public List<Device> queryDevices(String topologyID) {
      *
      * @param topologyID    String variable containing the topology ID
      * @param netlistNodeID String variable containing the node ID
-     * @return Returns a List of Device containing all connected devices. Returns an empty list if no devices are found.
+     * @return Returns a List of Device containing all connected devices.
+     * Returns an empty list if no devices are found.
      */
     public List<Device> queryDevicesWithNetlistNode(String topologyID, String netlistNodeID) {
         Topology topology = topologyRegistry.findTopology(topologyID);

src/main/java/com/github/khalidzahra/internal/device/Device.java

@@ -3,28 +3,29 @@
 import com.github.khalidzahra.internal.util.JsonKeyUtil;
 import com.google.gson.annotations.SerializedName;
 
-import java.util.HashMap;
+import java.util.Map;
 
 /**
  * Created by Khalid on 9/28/21.
  */
 public class Device {
 
-    @SerializedName(value = JsonKeyUtil.DEVICE_TYPE_KEY)
-    private DeviceType deviceType;
-    private String id;
+    @SerializedName(JsonKeyUtil.DEVICE_TYPE_KEY)
+    private final DeviceType deviceType;
+    @SerializedName("id")
+    private final String deviceId;
     @SerializedName(value = JsonKeyUtil.DEVICE_PROPERTIES_KEY,
             alternate = {JsonKeyUtil.DEVICE_PROPERTIES_RESISTANCE_KEY,
                     JsonKeyUtil.DEVICE_PROPERTIES_CAPACITANCE_KEY,
                     JsonKeyUtil.DEVICE_PROPERTIES_INDUCTANCE_KEY,
                     JsonKeyUtil.DEVICE_PROPERTIES_TRANSISTOR_KEY})
-    private DeviceProperties deviceProperties;
-    @SerializedName(value = JsonKeyUtil.DEVICE_NETLIST_KEY)
-    private HashMap<String, String> netList;
+    private final DeviceProperties deviceProperties;
+    @SerializedName(JsonKeyUtil.DEVICE_NETLIST_KEY)
+    private final Map<String, String> netList;
 
-    public Device(DeviceType deviceType, String id, DeviceProperties deviceProperties, HashMap<String, String> netList) {
+    public Device(DeviceType deviceType, String deviceId, DeviceProperties deviceProperties, Map<String, String> netList) {
         this.deviceType = deviceType;
-        this.id = id;
+        this.deviceId = deviceId;
         this.deviceProperties = deviceProperties;
         this.netList = netList;
     }
@@ -33,15 +34,15 @@ public DeviceType getDeviceType() {
         return deviceType;
     }
 
-    public String getId() {
-        return id;
+    public String getDeviceId() {
+        return deviceId;
     }
 
     public DeviceProperties getDeviceProperties() {
         return deviceProperties;
     }
 
-    public HashMap<String, String> getNetList() {
+    public Map<String, String> getNetList() {
         return netList;
     }
 }

src/main/java/com/github/khalidzahra/internal/device/DeviceProperties.java

@@ -7,11 +7,18 @@
  */
 public class DeviceProperties {
 
-    private double min, max;
+    private double min;
+    private double max;
 
     @SerializedName("default")
     private double defaultValue;
 
+    public DeviceProperties(double min, double max, double defaultValue) {
+        this.min = min;
+        this.max = max;
+        this.defaultValue = defaultValue;
+    }
+
     public double getMin() {
         return min;
     }

src/main/java/com/github/khalidzahra/internal/topology/Topology.java

@@ -11,17 +11,18 @@
  */
 public class Topology {
 
-    private String id;
+    @SerializedName("id")
+    private final String topologyId;
     @SerializedName("components")
-    private List<Device> devices;
+    private final List<Device> devices;
 
-    public Topology(String id) {
-        this.id = id;
+    public Topology(String topologyId) {
+        this.topologyId = topologyId;
         this.devices = new ArrayList<>();
     }
 
-    public Topology(String id, List<Device> deviceList) {
-        this.id = id;
+    public Topology(String topologyId, List<Device> deviceList) {
+        this.topologyId = topologyId;
         this.devices = deviceList;
     }
 
@@ -42,8 +43,8 @@ public void addDevice(Device device) {
         devices.add(device);
     }
 
-    public String getId() {
-        return id;
+    public String getTopologyId() {
+        return topologyId;
     }
 
     public List<Device> getDevices() {

src/main/java/com/github/khalidzahra/internal/topology/TopologyRegistry.java

@@ -1,6 +1,6 @@
 package com.github.khalidzahra.internal.topology;
 
-import com.github.khalidzahra.internal.util.json.GsonHandler;
+import com.github.khalidzahra.internal.util.json.GsonUtil;
 
 import java.util.ArrayList;
 import java.util.List;
@@ -18,53 +18,64 @@ public TopologyRegistry() {
 
     /**
      * Loads the topology from the specified file and adds it to topologyList.
+     *
      * @param filePath String variable containing path to the JSON file
      * @return Returns true if the topology is successfully loaded and registered
      */
     public boolean loadAndRegisterTopology(String filePath) {
-        Topology topology = GsonHandler.loadTopology(filePath);
+        Topology topology = GsonUtil.loadTopology(filePath);
         return registerTopology(topology);
     }
 
     /**
      * Writes the specified topology to the specified file
+     *
      * @param topologyID String variable containing the topology ID
-     * @param filePath String variable containing path to the JSON file
+     * @param filePath   String variable containing path to the JSON file
      * @return Returns true if the topology is successfully found and saved
      */
     public boolean saveTopology(String topologyID, String filePath) {
         Topology topology = findTopology(topologyID);
-        if (topology == null) return false;
-        return GsonHandler.saveTopology(filePath, topology);
+        if (topology == null) {
+            return false;
+        }
+        return GsonUtil.saveTopology(filePath, topology);
     }
 
     /**
      * Adds the topology to topologyList
+     *
      * @param topology Topology object to be registered
      * @return Returns true if the topology is successfully registered
      */
     public boolean registerTopology(Topology topology) {
-        if (topology == null) return false;
+        if (topology == null) {
+            return false;
+        }
         return topologyList.add(topology);
     }
 
     /**
      * Finds the topology matching the specified ID
+     *
      * @param topologyID String variable containing the topology ID
      * @return Returns Topology object matching the specified ID. Returns null if no object matching the ID is found.
      */
     public Topology findTopology(String topologyID) {
-        return topologyList.stream().filter(topology -> topology.getId().equals(topologyID)).findAny().orElse(null);
+        return topologyList.stream().filter(topology -> topology.getTopologyId().equals(topologyID)).findAny().orElse(null);
     }
 
     /**
      * Unloads the topology from memory
+     *
      * @param topologyID String variable containing the topology ID
      * @return Returns true if topology is successfully found and unloaded.
      */
     public boolean deregisterTopology(String topologyID) {
         Topology topology = findTopology(topologyID);
-        if (topology == null) return false;
+        if (topology == null) {
+            return false;
+        }
         return topologyList.remove(topology);
     }
 

src/main/java/com/github/khalidzahra/internal/util/json/DeviceSerializer.java

@@ -21,7 +21,7 @@ public class DeviceSerializer implements JsonSerializer<Device> {
     public JsonElement serialize(Device device, Type type, JsonSerializationContext jsonSerializationContext) {
         JsonObject jsonObject = new JsonObject();
         jsonObject.addProperty(JsonKeyUtil.DEVICE_TYPE_KEY, device.getDeviceType().toString().toLowerCase(Locale.ROOT));
-        jsonObject.addProperty("id", device.getId());
+        jsonObject.addProperty("id", device.getDeviceId());
         jsonObject.add(device.getDeviceType().getSerializedPropertyName(), jsonSerializationContext.serialize(device.getDeviceProperties()));
         jsonObject.add(JsonKeyUtil.DEVICE_NETLIST_KEY, jsonSerializationContext.serialize(device.getNetList()));
 

src/main/java/com/github/khalidzahra/internal/util/json/GsonHandler.java → src/main/java/com/github/khalidzahra/internal/util/json/GsonUtil.java

@@ -6,16 +6,18 @@
 import com.google.gson.GsonBuilder;
 
 import java.io.*;
+import java.nio.file.Files;
+import java.nio.file.Paths;
 
 /**
  * Created by Khalid on 9/28/21.
  */
-public class GsonHandler {
+public class GsonUtil {
 
     /**
      * GsonBuilder object that will be used throughout project
      */
-    private static final Gson gson = new GsonBuilder()
+    private static final Gson GSON_OBJECT = new GsonBuilder()
             .registerTypeAdapter(Device.class, new DeviceSerializer())
             .setPrettyPrinting().create();
 
@@ -27,10 +29,9 @@ public class GsonHandler {
      */
     public static Topology loadTopology(String filePath) {
         Topology topology;
-        try {
-            BufferedReader reader = new BufferedReader(new FileReader(filePath));
+        try (BufferedReader reader = Files.newBufferedReader(Paths.get(filePath))) {
             topology = getGson().fromJson(reader, Topology.class);
-        } catch (FileNotFoundException e) {
+        } catch (IOException e) {
             return null;
         }
         return topology;
@@ -44,7 +45,7 @@ public static Topology loadTopology(String filePath) {
      * @return Returns true if save was successful
      */
     public static boolean saveTopology(String filePath, Topology topology) {
-        try (FileWriter writer = new FileWriter(filePath)) {
+        try (BufferedWriter writer = Files.newBufferedWriter(Paths.get(filePath))) {
             getGson().toJson(topology, writer);
         } catch (IOException e) {
             return false;
@@ -53,6 +54,6 @@ public static boolean saveTopology(String filePath, Topology topology) {
     }
 
     public static Gson getGson() {
-        return gson;
+        return GSON_OBJECT;
     }
 }