Blackberry j2me openOutputStream流已打开
我在HttpConnection向我的服务器发布数据时遇到困难。第一次一切顺利。第二次,它说:流已经打开,但我在响应后关闭所有内容 这是我的密码:Blackberry j2me openOutputStream流已打开,blackberry,post,java-me,outputstream,httpconnection,Blackberry,Post,Java Me,Outputstream,Httpconnection,我在HttpConnection向我的服务器发布数据时遇到困难。第一次一切顺利。第二次,它说:流已经打开,但我在响应后关闭所有内容 这是我的密码: import javax.microedition.io.Connector; import javax.microedition.io.HttpConnection; import javax.microedition.location.*; import java.io.*; class GetSnowheights { Htt
import javax.microedition.io.Connector;
import javax.microedition.io.HttpConnection;
import javax.microedition.location.*;
import java.io.*;
class GetSnowheights
{
HttpConnection http = null;
QualifiedCoordinates q = null;
public String result = "Geen data";
private boolean running;
public GetSnowheights(QualifiedCoordinates q) {
try
{
/*
this.http = (HttpConnection)Connector.open("http://www.diamond4it.nl/bb/");
this.http.setRequestMethod(HttpConnection.POST);
this.http.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");
*/
//Internet.getInstance();
this.http = Internet.getConnection();
}catch(Exception err){
err.printStackTrace();
}
this.q = q;
this.result = "Running";
}
public void GetResult(){
StringBuffer sb = new StringBuffer();
this.result = "GetResult";
if(this.http != null){
OutputStream os = null;
InputStream is = null;
try
{
//Send request
os = this.http.openOutputStream();
String data = "lat=1&lng=1";
//String data = "lat=" + this.q.getLatitude() + "&lng=" + this.q.getLongitude();
os.write(data.getBytes());
os.flush();
os.close();
this.result = "dataSend";
//Check response and read data
int res = this.http.getResponseCode();
this.result = "Result: " + res;
if(res == 200){
is = this.http.openInputStream();
int ch;
// Check the Content-Length first
long len = this.http.getLength();
if(len!=-1) {
for(int i = 0;i<len;i++){
if((ch = is.read())!= -1){
sb.append((char)ch);
}
}
} else {
// if the content-length is not available
while ((ch = is.read()) != -1){
sb.append((char)ch);
}
}
is.close();
}
this.result = sb.toString();
}catch(Exception err){
//err.printStackTrace();
this.result = err.toString() + "\r\n" + err.getMessage();
}finally{
if(is != null){
try{
is.close();
}catch(Exception err){
err.printStackTrace();
}
}
if(os != null){
try{
//os.flush();
os.close();
}catch(Exception err){
err.printStackTrace();
}
}
/*
if(http != null){
try{
http.close();
}catch(Exception err){
err.printStackTrace();
}
}
*/
}
}else{
this.result = "No connection";
}
}
}
2个想法:
为什么要注释掉http.close-in-finally块?我们应该始终关闭http连接
您不是同时从多个线程调用GetResult吗?如果是,则通过在其定义中添加synchronized关键字使方法同步
另外,我觉得这个班级的设计有点误导。不正确地使用它很容易犯错误。我会将GetSnowheights和GetResult合并到唯一的同步方法中。不工作。还是一样的信息。即使使用了sinchronized voidity,我也不知道该怎么做。你想重用这个。http吗?也就是说,您是否多次调用GetResult而没有获得新的HttpConnection?我认为这是不允许的。这是一个单例类的Internet,它返回一个有效的httpconnection。http在这个类中是私有的,所以是的,我重用它。好的,那么您对GetSnowheights类的每个实例调用GetResult不止一次?这意味着您正在尝试重用HttpConnection。我自己从来没有这样做过,但我觉得这是一个潜在的问题。如果在每次调用GetResult之前重构代码以创建一个新的GetSnowheights实例呢?