diff --git a/effective-java/src/main/java/com/example/effectivejava/chapter01/item02/freeze/Person.java b/effective-java/src/main/java/com/example/effectivejava/chapter01/item02/freeze/Person.java
new file mode 100644
index 00000000..49b88b3e
--- /dev/null
+++ b/effective-java/src/main/java/com/example/effectivejava/chapter01/item02/freeze/Person.java
@@ -0,0 +1,23 @@
+package com.example.effectivejava.chapter01.item02.freeze;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public class Person {
+
+    private final String name;
+
+    private final int birthYear;
+
+    private final List<String> kids;
+
+    public Person(String name, int birthYear) {
+        this.name = name;
+        this.birthYear = birthYear;
+        this.kids = new ArrayList<>();
+    }
+
+    public static void main(String[] args) {
+
+    }
+}
\ No newline at end of file
diff --git a/effective-java/src/main/java/com/example/effectivejava/chapter01/item02/hierarchicalbuilder/NyPizza.java b/effective-java/src/main/java/com/example/effectivejava/chapter01/item02/hierarchicalbuilder/NyPizza.java
index 94268df2..55cc6706 100644
--- a/effective-java/src/main/java/com/example/effectivejava/chapter01/item02/hierarchicalbuilder/NyPizza.java
+++ b/effective-java/src/main/java/com/example/effectivejava/chapter01/item02/hierarchicalbuilder/NyPizza.java
@@ -1,5 +1,7 @@
 package com.example.effectivejava.chapter01.item02.hierarchicalbuilder;
 
+import java.util.Objects;
+
 // 코드 2-5 뉴욕 피자 - 계층적 빌더를 활용한 하위 클래스 (20쪽)
 public class NyPizza extends Pizza {
     public enum Size { SMALL, MEDIUM, LARGE }
diff --git a/effective-java/src/main/java/com/example/effectivejava/chapter01/item02/illegalargumentexception/Order.java b/effective-java/src/main/java/com/example/effectivejava/chapter01/item02/illegalargumentexception/Order.java
new file mode 100644
index 00000000..c0be65ad
--- /dev/null
+++ b/effective-java/src/main/java/com/example/effectivejava/chapter01/item02/illegalargumentexception/Order.java
@@ -0,0 +1,19 @@
+package com.example.effectivejava.chapter01.item02.illegalargumentexception;
+
+import java.time.LocalDate;
+
+public class Order {
+
+    public void updateDeliveryDate(LocalDate deliveryDate) {
+        if (deliveryDate == null) {
+            throw new NullPointerException("deliveryDate can't be null");
+        }
+
+        if (deliveryDate.isBefore(LocalDate.now())) {
+             throw new IllegalArgumentException("deliveryDate can't be earlier than " + LocalDate.now());
+        }
+
+        // 배송 날짜 업데이트
+    }
+
+}
\ No newline at end of file
diff --git a/effective-java/src/main/java/com/example/effectivejava/chapter01/item02/varargs/VarargsSamples.java b/effective-java/src/main/java/com/example/effectivejava/chapter01/item02/varargs/VarargsSamples.java
new file mode 100644
index 00000000..ef00b1e6
--- /dev/null
+++ b/effective-java/src/main/java/com/example/effectivejava/chapter01/item02/varargs/VarargsSamples.java
@@ -0,0 +1,17 @@
+package com.example.effectivejava.chapter01.item02.varargs;
+
+import java.util.Arrays;
+
+public class VarargsSamples {
+
+    public void printNumbers(int... numbers) {
+        System.out.println(numbers.getClass().getCanonicalName());
+        System.out.println(numbers.getClass().getComponentType());
+        Arrays.stream(numbers).forEach(System.out::println);
+    }
+
+    public static void main(String[] args) {
+        VarargsSamples samples = new VarargsSamples();
+        samples.printNumbers(1, 20, 20, 39, 59);
+    }
+}
\ No newline at end of file