diff --git a/bin/j2/EchoClient.class b/bin/j2/EchoClient.class
index 52d0a38..b6ed968 100644
--- a/bin/j2/EchoClient.class
+++ b/bin/j2/EchoClient.class
Binary files differ
diff --git a/bin/j2/EchoServer.class b/bin/j2/EchoServer.class
index e7783aa..59c4009 100644
--- a/bin/j2/EchoServer.class
+++ b/bin/j2/EchoServer.class
Binary files differ
diff --git a/src/j2/EchoClient.java b/src/j2/EchoClient.java
index 9f82632..4681f06 100644
--- a/src/j2/EchoClient.java
+++ b/src/j2/EchoClient.java
@@ -1,10 +1,14 @@
 package j2;
 
-import java.io.*;
-import java.net.*;
+import java.io.BufferedReader;
+import java.io.DataOutputStream;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.net.Socket;
+import java.net.UnknownHostException;
 public class EchoClient {
     public static void main(String[] args) {
-        //　ソケットや入出力用のストリームの宣言
+        // ソケットや入出力用のストリームの宣言
         Socket echoSocket = null;
         DataOutputStream os = null;
         BufferedReader is = null;
diff --git a/src/j2/EchoServer.java b/src/j2/EchoServer.java
index 9aad251..64f73ec 100644
--- a/src/j2/EchoServer.java
+++ b/src/j2/EchoServer.java
@@ -1,7 +1,11 @@
 package j2;
 
-import java.io.*;
-import java.net.*;
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.io.PrintStream;
+import java.net.ServerSocket;
+import java.net.Socket;
  
 public class EchoServer {
     public static void main(String args[]) {