toString() unavailable，

toString() unavailable，

package test.socket;


import java.io.BufferedReader;
import java.io.DataInputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.net.ServerSocket;
import java.net.Socket;


public class Server {


public void startServer(int port) {


DataInputStream in = null;
OutputStream out = null;
BufferedReader reader = null;
try {
ServerSocket server = new ServerSocket(port);
// while (true) {
Socket client = server.accept();
in = new DataInputStream(client.getInputStream());


// 获取客户端请求信息
reader = new BufferedReader(
new InputStreamReader(in));

// 执行到此出现toString() unavailable - no suspended threads
String line = reader.readLine();

if (line != null && !"".equals(line)) {
System.out.println(line);
} else {
System.out.println("null or empty");
}

// Thread.sleep(1000);
//server-->client
out = client.getOutputStream();
out.write("server response to client".getBytes());
out.flush();
//}
client.close();
} catch (Exception e) {
e.printStackTrace();
} finally {
try {
if (in != null) {
in.close();
}
if (out != null) {
out.close();
}
if (reader != null) {
reader.close();
}
} catch (IOException e) {
e.printStackTrace();
}
}
}


public static void main(String[] args) {
Server server = new Server();
server.startServer(8888);
}

}

package test.socket;


import java.io.BufferedReader;
import java.io.DataInputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.net.Socket;


public class Client {


public static void main(String[] args) {
OutputStream out = null;
DataInputStream in = null;
BufferedReader reader = null;
try {
Socket client = new Socket("localhost", 8888);


out = client.getOutputStream();
out.write("request to server".getBytes());
out.flush();

in = new DataInputStream(client.getInputStream());
reader = new BufferedReader(
new InputStreamReader(in));
System.out.println(">>>>>"+reader.readLine());


}catch (Exception e) {
e.printStackTrace();
} finally {
try {
if (in != null) {
in.close();
}
if (out != null) {
out.close();
}
if (reader != null) {
reader.close();
}
} catch (IOException e) {
e.printStackTrace();
}
}
}
}

没明白红色字标注的地方，会出现toString() unavailable - no suspended threads

问题在：line = reader.readLine();

API里面的描述：

Read a line of text.  A line is considered to be terminated by any one of a line feed ('\n'), a carriage return ('\r'), or a carriage return followed immediately by a linefeed.

必须以“\n” 和“\r”作为一行的结束符。

下面修改下，就可解决了：

server.java 中：out.write("server response to client".getBytes());--->out.write("server response to client\n".getBytes());

client.java 中：out.write("request to server".getBytes());---->out.write("request to server\n".getBytes());