add

Author: Bascy6

app/src/main/java/hexlet/code/App.java

@@ -1,7 +1,7 @@
 package hexlet.code;
 
-import hexlet.code.schemas.BaseSchema;
 import hexlet.code.schemas.MapSchema;
+import hexlet.code.schemas.BaseSchema;
 
 import java.util.HashMap;
 import java.util.Map;
@@ -22,12 +22,12 @@ public static void main(String[] args) {
         human1.put("name", "Alice");
         human1.put("age", 25);
 
-        System.out.println(schema.isValid(human1));
+        System.out.println(schema.isValid(human1)); // true
 
         Map<String, Object> human2 = new HashMap<>();
         human2.put("name", "Bob");
         human2.put("age", -5);
 
-        System.out.println(schema.isValid(human2));
+        System.out.println(schema.isValid(human2)); // false
     }
 }

app/src/main/java/hexlet/code/schemas/BaseSchema.java

@@ -1,17 +1,16 @@
 package hexlet.code.schemas;
 
-public abstract class BaseSchema<T> {
+public abstract class BaseSchema<T extends BaseSchema<T>> {
     protected boolean isRequired = false;
 
     public T required() {
         this.isRequired = true;
         return (T) this;
     }
 
-    public boolean isValid(Object value) {
-        if (isRequired && value == null) {
-            return false;
-        }
-        return true;
+    protected boolean checkRequired(Object value) {
+        return !isRequired || value != null;
     }
+
+    public abstract boolean isValid(Object value);
 }

app/src/main/java/hexlet/code/schemas/MapSchema.java

@@ -8,11 +8,11 @@ public class MapSchema extends BaseSchema<MapSchema> {
 
     @Override
     public boolean isValid(Object value) {
-        if (!super.isValid(value)) {
+        if (!checkRequired(value)) {
             return false;
         }
         if (value == null) {
-            return !isRequired;
+            return true;
         }
         if (!(value instanceof Map)) {
             return false;

app/src/main/java/hexlet/code/schemas/NumberSchema.java

@@ -18,7 +18,7 @@ public NumberSchema range(int min, int max) {
 
     @Override
     public boolean isValid(Object value) {
-        if (!super.isValid(value)) {
+        if (!checkRequired(value)) {
             return false;
         }
         if (value == null) {

app/src/main/java/hexlet/code/schemas/StringSchema.java

@@ -16,11 +16,11 @@ public StringSchema contains(String substring) {
 
     @Override
     public boolean isValid(Object value) {
-        if (!super.isValid(value)) {
+        if (!checkRequired(value)) {
             return false;
         }
         if (value == null) {
-            return !isRequired;
+            return true;
         }
         if (!(value instanceof String)) {
             return false;