diff --git a/bin/j2/EchoClient.class b/bin/j2/EchoClient.class
deleted file mode 100644
index db3503c..0000000
--- a/bin/j2/EchoClient.class
+++ /dev/null
Binary files differ
diff --git a/src/j2/EchoClient.java b/src/j2/EchoClient.java
index f2c86f1..67f5782 100644
--- a/src/j2/EchoClient.java
+++ b/src/j2/EchoClient.java
@@ -14,14 +14,15 @@
         BufferedReader is = null;
         
         // ポート9999番を開く
+    	String host = "localhost";
         try {
-            echoSocket = new Socket("localhost", 9999);
+            echoSocket = new Socket(host, 9999);
             os = new DataOutputStream(echoSocket.getOutputStream());
             is = new BufferedReader(new InputStreamReader(echoSocket.getInputStream()));
         } catch (UnknownHostException e) {
-            System.err.println("Don't know about host: localhost");
+            System.err.println("Don't know about host: "+host);
         } catch (IOException e) {
-            System.err.println("Couldn't get I/O for the connection to: localhost");
+            System.err.println("Couldn't get I/O for the connection to: "+host);
         }
 
         // サーバーにメッセージを送る
diff --git a/src/j2/ThreadEchoClient.java b/src/j2/ThreadEchoClient.java
new file mode 100644
index 0000000..64e9021
--- /dev/null
+++ b/src/j2/ThreadEchoClient.java
@@ -0,0 +1,58 @@
+package j2;
+
+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 ThreadEchoClient {
+    public static void main(String[] args) {
+        // 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;
+        BufferedReader inputbr = null;
+        
+        // ポート9999番を開く
+    	String host = "localhost";
+        try {
+            echoSocket = new Socket(host, 9999);
+            os = new DataOutputStream(echoSocket.getOutputStream());
+            is = new BufferedReader(new InputStreamReader(echoSocket.getInputStream()));
+            inputbr = new BufferedReader(new InputStreamReader(System.in));
+        } catch (UnknownHostException e) {
+            System.err.println("Don't know about host: "+host);
+        } catch (IOException e) {
+            System.err.println("Couldn't get I/O for the connection to: "+host);
+        }
+
+        // サーバーにメッセージを送る
+        if (echoSocket != null && os != null && is != null) {
+            try {
+                // メッセージを送ります
+                os.writeBytes("HELLO\n");
+
+                // サーバーからのメッセージを受け取り画面に表示します
+                String line;
+                while ((line = is.readLine()) != null) {
+                    System.out.println("Server: " + line);
+                    if (line.equals("quit")) break;
+                    if (inputbr.ready()) {
+                    	String s = inputbr.readLine();
+                        os.writeBytes(s+"\n");
+                    }
+                }
+
+                // 開いたソケットなどをクローズ
+                os.close();
+                is.close();
+                echoSocket.close();
+            } catch (UnknownHostException e) {
+                System.err.println("Trying to connect to unknown host: " + e);
+            } catch (IOException e) {
+                System.err.println("IOException: " + e);
+            }
+        }
+    }
+}
\ No newline at end of file