External store api.

Author: IzzelAliz

src/api/java/io/izzel/mesmerize/api/visitor/ValueVisitor.java

@@ -27,7 +27,7 @@ public interface ValueVisitor {
 
     void visitEnd();
 
-    boolean hasExternalValue();
+    StatsValue<?> getExternalValue();
 
     default EventContext context() {
         return CauseManager.instance().currentContext();

src/api/java/io/izzel/mesmerize/api/visitor/impl/AbstractValue.java

@@ -78,8 +78,8 @@ public void visitEnd() {
     }
 
     @Override
-    public boolean hasExternalValue() {
-        return false;
+    public StatsValue<?> getExternalValue() {
+        throw new UnsupportedOperationException("external");
     }
 
     public static <V extends AbstractValue<?>> BiFunction<V, V, V> keepMutableValue(BiFunction<V, V, V> merger) {

src/api/java/io/izzel/mesmerize/api/visitor/impl/AbstractValueVisitor.java

@@ -2,6 +2,7 @@
 
 import io.izzel.mesmerize.api.visitor.ListVisitor;
 import io.izzel.mesmerize.api.visitor.MapVisitor;
+import io.izzel.mesmerize.api.visitor.StatsValue;
 import io.izzel.mesmerize.api.visitor.StatsVisitor;
 import io.izzel.mesmerize.api.visitor.ValueVisitor;
 
@@ -117,10 +118,10 @@ public void visitEnd() {
     }
 
     @Override
-    public boolean hasExternalValue() {
+    public StatsValue<?> getExternalValue() {
         if (visitor != null) {
-            return visitor.hasExternalValue();
+            return visitor.getExternalValue();
         }
-        return false;
+        return null;
     }
 }

src/main/java/io/izzel/mesmerize/impl/config/YamlValueReader.java

@@ -1,9 +1,9 @@
 package io.izzel.mesmerize.impl.config;
 
+import io.izzel.mesmerize.api.visitor.StatsValue;
 import io.izzel.mesmerize.api.visitor.ValueVisitor;
 import io.izzel.mesmerize.api.visitor.VisitMode;
 import io.izzel.mesmerize.api.visitor.impl.AbstractValue;
-import io.izzel.mesmerize.impl.util.visitor.external.ExternalTrackingVisitor;
 import org.bukkit.configuration.ConfigurationSection;
 
 import java.util.Collection;
@@ -24,8 +24,9 @@ public YamlValueReader(Object o) {
     @SuppressWarnings("unchecked")
     @Override
     public void accept(ValueVisitor visitor, VisitMode mode) {
-        if (visitor instanceof ExternalTrackingVisitor && visitor.hasExternalValue()) {
-            ((ExternalTrackingVisitor) visitor).getExternal().accept(visitor, mode);
+        StatsValue<?> externalValue = visitor.getExternalValue();
+        if (externalValue != null) {
+            externalValue.accept(visitor, mode);
             return;
         }
         if (o instanceof Boolean) {

src/main/java/io/izzel/mesmerize/impl/util/visitor/PersistentValueReader.java

@@ -1,11 +1,11 @@
 package io.izzel.mesmerize.impl.util.visitor;
 
 import io.izzel.mesmerize.api.visitor.ListVisitor;
+import io.izzel.mesmerize.api.visitor.StatsValue;
 import io.izzel.mesmerize.api.visitor.ValueVisitor;
 import io.izzel.mesmerize.api.visitor.VisitMode;
 import io.izzel.mesmerize.api.visitor.impl.AbstractValue;
 import io.izzel.mesmerize.impl.util.Util;
-import io.izzel.mesmerize.impl.util.visitor.external.ExternalTrackingVisitor;
 import org.bukkit.NamespacedKey;
 import org.bukkit.persistence.PersistentDataContainer;
 import org.bukkit.persistence.PersistentDataType;
@@ -23,8 +23,9 @@ public PersistentValueReader(PersistentDataContainer container, NamespacedKey ke
     @SuppressWarnings("ConstantConditions")
     @Override
     public void accept(ValueVisitor visitor, VisitMode mode) {
-        if (visitor instanceof ExternalTrackingVisitor && visitor.hasExternalValue()) {
-            ((ExternalTrackingVisitor) visitor).getExternal().accept(visitor, mode);
+        StatsValue<?> externalValue = visitor.getExternalValue();
+        if (externalValue != null) {
+            externalValue.accept(visitor, mode);
             return;
         }
         int i = Util.typeOfKey(this.container, this.key);

src/main/java/io/izzel/mesmerize/impl/util/visitor/external/ExternalReader.java

@@ -1,5 +1,6 @@
 package io.izzel.mesmerize.impl.util.visitor.external;
 
+import io.izzel.mesmerize.api.visitor.StatsValue;
 import io.izzel.mesmerize.api.visitor.ValueVisitor;
 import io.izzel.mesmerize.api.visitor.VisitMode;
 import io.izzel.mesmerize.api.visitor.impl.AbstractValue;
@@ -29,14 +30,20 @@ public ExternalReader child(NamespacedKey key) {
         if (container == null || key == null) {
             return this;
         } else {
-            return new ExternalReader(container.get(key, PersistentDataType.TAG_CONTAINER));
+            PersistentDataContainer container = this.container.get(key, PersistentDataType.TAG_CONTAINER);
+            return container == null ? null : new ExternalReader(container);
         }
     }
 
     @Override
     public void accept(ValueVisitor visitor, VisitMode mode) {
         if (container != null) {
-            new PersistentValueReader(container, VALUE).accept(new AbstractValueVisitor(visitor), mode);
+            new PersistentValueReader(container, VALUE).accept(new AbstractValueVisitor(visitor) {
+                @Override
+                public StatsValue<?> getExternalValue() {
+                    return null;
+                }
+            }, mode);
         } else {
             visitor.visitEnd();
         }

src/main/java/io/izzel/mesmerize/impl/util/visitor/external/ExternalTrackingVisitor.java

@@ -15,8 +15,6 @@
 
 public interface ExternalTrackingVisitor {
 
-    ExternalReader getExternal();
-
     class ValueTracker extends AbstractValueVisitor implements ExternalTrackingVisitor {
 
         private final ExternalReader reader;
@@ -27,7 +25,7 @@ public ValueTracker(ValueVisitor visitor, ExternalReader reader) {
         }
 
         @Override
-        public ExternalReader getExternal() {
+        public ExternalReader getExternalValue() {
             return reader;
         }
 
@@ -60,11 +58,6 @@ public MapTracker(MapVisitor visitor, ExternalReader reader) {
         public ValueVisitor visit(String key) {
             return new ValueTracker(super.visit(key), reader.child(Util.fromString(key)));
         }
-
-        @Override
-        public ExternalReader getExternal() {
-            return reader;
-        }
     }
 
     class ListTracker extends AbstractListVisitor implements ExternalTrackingVisitor {
@@ -80,11 +73,6 @@ public ListTracker(ListVisitor visitor, ExternalReader reader) {
         public ValueVisitor visit(int index) {
             return new ValueTracker(super.visit(index), reader.child(NamespacedKey.minecraft(String.valueOf(index))));
         }
-
-        @Override
-        public ExternalReader getExternal() {
-            return reader;
-        }
     }
 
     class StatsTracker extends AbstractStatsVisitor implements ExternalTrackingVisitor {
@@ -100,10 +88,5 @@ public StatsTracker(StatsVisitor visitor, ExternalReader reader) {
         public <T> ValueVisitor visitStats(@NotNull Stats<T> stats) {
             return new ValueTracker(super.visitStats(stats), reader.child(stats.getKey()));
         }
-
-        @Override
-        public ExternalReader getExternal() {
-            return reader;
-        }
     }
 }