diff --git a/src/main/java/proto/A.java b/src/main/java/proto/A.java
deleted file mode 100644
index 8ddcccb..0000000
--- a/src/main/java/proto/A.java
+++ /dev/null
@@ -1,17 +0,0 @@
-package proto;
-
-public class A {
-	protected int a;
-
-	public A(int a) {
-		this.a = a;
-	}
-
-	public int get() {
-		return a;
-	}
-
-	public void set(int a) {
-		this.a = a;
-	}
-}
diff --git a/src/main/java/proto/B.java b/src/main/java/proto/B.java
deleted file mode 100644
index 079b7d8..0000000
--- a/src/main/java/proto/B.java
+++ /dev/null
@@ -1,10 +0,0 @@
-package proto;
-
-public class B extends A {
-
-	public B(int a) {
-		super(a);
-		// TODO 自動生成されたコンストラクター・スタブ
-	}
-
-}
diff --git a/src/main/java/proto/C.java b/src/main/java/proto/C.java
deleted file mode 100644
index c27ee5e..0000000
--- a/src/main/java/proto/C.java
+++ /dev/null
@@ -1,10 +0,0 @@
-package proto;
-
-public class C extends A{
-
-	public C(int a) {
-		super(a);
-		// TODO 自動生成されたコンストラクター・スタブ
-	}
-
-}
diff --git a/src/main/java/proto/Company.java b/src/main/java/proto/Company.java
new file mode 100644
index 0000000..596187a
--- /dev/null
+++ b/src/main/java/proto/Company.java
@@ -0,0 +1,9 @@
+package proto;
+
+public class Company {
+	public String address;
+
+	public Company(String address) {
+		this.address = address;
+	}
+}
diff --git a/src/main/java/proto/Customer.java b/src/main/java/proto/Customer.java
new file mode 100644
index 0000000..f14c727
--- /dev/null
+++ b/src/main/java/proto/Customer.java
@@ -0,0 +1,11 @@
+package proto;
+
+public class Customer {
+	public String company;
+	public String address;
+
+	public Customer(String company, String address) {
+		this.company = company;
+		this.address = address;
+	}
+}
diff --git a/src/main/java/proto/D.java b/src/main/java/proto/D.java
deleted file mode 100644
index 2a5578c..0000000
--- a/src/main/java/proto/D.java
+++ /dev/null
@@ -1,10 +0,0 @@
-package proto;
-
-public class D extends A{
-
-	public D(int a) {
-		super(a);
-		// TODO 自動生成されたコンストラクター・スタブ
-	}
-
-}
diff --git a/src/main/java/proto/Main.java b/src/main/java/proto/Main.java
index b064fdc..95c17d6 100644
--- a/src/main/java/proto/Main.java
+++ b/src/main/java/proto/Main.java
@@ -1,17 +1,8 @@
 package proto;
-import javax.swing.JFrame;
-
 public class Main {
 
 	public static void main(String[] args) {
-		A ins[] = { new A(10), new B(5), new C(7), new D(8) };
-		for (int i = 0; i < 4; i++) {
-			System.out.println(ins[i].get());
-		}
-		JFrame frame=new JFrame("test");
-	    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
-	    frame.setSize(400,400);
-	    frame.setVisible(true);
+		
 	}
 
 }
diff --git a/src/main/java/proto/System.java b/src/main/java/proto/System.java
new file mode 100644
index 0000000..e069368
--- /dev/null
+++ b/src/main/java/proto/System.java
@@ -0,0 +1,9 @@
+package proto;
+
+import java.util.HashMap;
+import java.util.Map;
+
+public class System {
+	static Map<String, Company> companies = new HashMap<>();
+	static Map<String, Customer> customers = new HashMap<>();
+}