Started to add Nullable/NonNull annotations

pom.xml

@@ -119,6 +119,15 @@
 			<version>2.9.2</version>
 			<scope>provided</scope>
 		</dependency>
+		<!-- Static analysis -->
+		<!-- We are using Eclipse's annotations.
+		If you're using IDEA, update your project settings to take these
+		into account for in real time static analysis -->
+        <dependency>
+            <groupId>org.eclipse.jdt</groupId>
+            <artifactId>org.eclipse.jdt.annotation</artifactId>
+            <version>2.2.200</version>
+        </dependency>
 	</dependencies>
 
 	<build>

src/main/java/world/bentobox/bentobox/api/logs/LogEntry.java

@@ -1,5 +1,8 @@
 package world.bentobox.bentobox.api.logs;
 
+import org.eclipse.jdt.annotation.NonNull;
+import org.eclipse.jdt.annotation.Nullable;
+
 import java.util.LinkedHashMap;
 import java.util.Locale;
 import java.util.Map;
@@ -17,7 +20,7 @@ public class LogEntry {
     private final String type;
     private final Map<String, Object> data;
 
-    private LogEntry(Builder builder) {
+    private LogEntry(@NonNull Builder builder) {
         this.timestamp = builder.timestamp;
         this.type = builder.type;
         this.data = builder.data;
@@ -27,10 +30,12 @@ public class LogEntry {
         return timestamp;
     }
 
+    @NonNull
     public String getType() {
         return type;
     }
 
+    @Nullable
     public Map<String, Object> getData() {
         return data;
     }
@@ -40,7 +45,7 @@ public class LogEntry {
         private String type;
         private Map<String, Object> data;
 
-        public Builder(String type) {
+        public Builder(@NonNull String type) {
             this.timestamp = System.currentTimeMillis();
             this.type = type.toUpperCase(Locale.ENGLISH);
             this.data = new LinkedHashMap<>();
@@ -51,7 +56,7 @@ public class LogEntry {
             return this;
         }
 
-        public Builder data(Map<String, Object> data) {
+        public Builder data(Map<@NonNull String, @Nullable Object> data) {
             this.data = data;
             return this;
         }
@@ -62,7 +67,7 @@ public class LogEntry {
          * @param value value to set
          * @return the Builder instance
          */
-        public Builder data(String key, Object value) {
+        public Builder data(@NonNull String key, @Nullable Object value) {
             this.data.put(key, value);
             return this;
         }

src/main/java/world/bentobox/bentobox/database/objects/Island.java

@@ -20,6 +20,8 @@ import com.google.common.collect.ImmutableSet;
 import com.google.common.collect.ImmutableSet.Builder;
 import com.google.gson.annotations.Expose;
 
+import org.eclipse.jdt.annotation.Nullable;
+import org.eclipse.jdt.annotation.NonNull;
 import world.bentobox.bentobox.BentoBox;
 import world.bentobox.bentobox.api.configuration.WorldSettings;
 import world.bentobox.bentobox.api.flags.Flag;
@@ -104,7 +106,7 @@ public class Island implements DataObject {
 
     public Island() {}
 
-    public Island(Location location, UUID owner, int protectionRange) {
+    public Island(@NonNull Location location, UUID owner, int protectionRange) {
         setOwner(owner);
         createdDate = System.currentTimeMillis();
         updatedDate = System.currentTimeMillis();
@@ -119,7 +121,7 @@ public class Island implements DataObject {
      * Adds a team member. If player is on banned list, they will be removed from it.
      * @param playerUUID - the player's UUID
      */
-    public void addMember(UUID playerUUID) {
+    public void addMember(@NonNull UUID playerUUID) {
         setRank(playerUUID, RanksManager.MEMBER_RANK);
     }
 
@@ -133,7 +135,7 @@ public class Island implements DataObject {
      * @param target UUID of the target, must be provided.
      * @return {@code true} if the target is successfully banned, {@code false} otherwise.
      */
-    public boolean ban(UUID issuer, UUID target) {
+    public boolean ban(@Nullable UUID issuer, @NonNull UUID target) {
         if (target != null) {
             setRank(target, RanksManager.BANNED_RANK);
             log(new LogEntry.Builder("BAN").data("player", target).data("issuer", issuer).build());
@@ -164,7 +166,7 @@ public class Island implements DataObject {
      * @param target UUID of the target, must be provided.
      * @return {@code true} if the target is successfully unbanned, {@code false} otherwise.
      */
-    public boolean unban(UUID issuer, UUID target) {
+    public boolean unban(@Nullable UUID issuer, @NonNull UUID target) {
         if (members.remove(target) != null) {
             log(new LogEntry.Builder("UNBAN").data("player", target).data("issuer", issuer).build());
             return true;
@@ -193,7 +195,7 @@ public class Island implements DataObject {
      * @param flag - flag
      * @return flag value
      */
-    public int getFlag(Flag flag) {
+    public int getFlag(@NonNull Flag flag) {
         flags.putIfAbsent(flag, flag.getDefaultRank());
         return flags.get(flag);
     }