<分区>
我正在创建 Android 应用程序，它调用我在服务器上创建的休息服务，并且服务器正在运行，但由于互联网连接问题，有时我的应用程序成功运行但有时它崩溃了。我的连接类的代码如下
public class CommunicationClass {
@SuppressWarnings("unused")
private static final String TAG = null;
public String Domain;
public HttpClient client;
public HttpPost datapost;
public HttpResponse response;
public BufferedReader reader;
public StringBuilder builder;
public JSONTokener tokener;
public JSONObject finalResult;
List<NameValuePair> namevaluepairs = new ArrayList<NameValuePair>(10);
public void setClient() {
// TODO Auto-generated method stub
client = new DefaultHttpClient();
System.out.println("Created http client");
}
public void setDomain(String st) {
// TODO Auto-generated method stub
Domain = st;
System.out.println("Domain has been set");
}
public void setResponse(){
response=null;
System.out.println("Response has been initalized by null");
}
public void setStringBuilder(){
builder = new StringBuilder();
}
public void setreader(){
try {
reader = new BufferedReader(new InputStreamReader(this.response.getEntity().getContent(), "UTF-8"));
System.out.println("Setting the contents of the Reader");
} catch (UnsupportedEncodingException e) {
// TODO Auto-generated catch block
System.out.println("In the UnsupportedEncodingException catch of the Reader");
e.printStackTrace();
} catch (IllegalStateException e) {
// TODO Auto-generated catch block
System.out.println("In the IllegalStateException catch of the Reader");
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
System.out.println("In the IOException catch of the Reader");
e.printStackTrace();
}
}
public void startpost(String str){
datapost=new HttpPost(str);
System.out.println("Created the httppost domain");
}
public void insertdata(String tag,String value){
namevaluepairs.add(new BasicNameValuePair(tag,value));
System.out.println("Added the parameter "+tag);
}
public void trydata(){
try {
this.datapost.setEntity(new UrlEncodedFormEntity(this.namevaluepairs));
System.out.println("Setting the entity");
try {
this.response = this.client.execute(this.datapost);
System.out.println("executing the client");
if(this.response != null){
System.out.println("i am in if of this.response!=null");
}
else{
System.out.println("i am in else of this.response!=null");
}
System.out.println("in response try box");
} catch (ClientProtocolException e) {
// TODO Auto-generated catch block
System.out.println("in ClientProtocolException Catch box");
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
System.out.println("in IOException Catch box");
e.printStackTrace();
}
} catch (UnsupportedEncodingException e) {
// TODO Auto-generated catch block
System.out.println("in UnSupported Catch box");
e.printStackTrace();
}
}
public void readresponse(){
try {
for (String line = null; (line = reader.readLine()) != null;) {
builder.append(line).append("\n");
}
System.out.println(this.builder);
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
tokener = new JSONTokener(builder.toString());
try {
finalResult = new JSONObject(tokener);
System.out.println("I am in try block of json final result reading");
} catch (JSONException e) {
// TODO Auto-generated catch block
System.out.println("I catch block of jsonException");
e.printStackTrace();
}
}
}
它在 trydata() 行给我错误；实际上执行 HTTP 客户端，所以我想确保它不会因互联网连接而崩溃，但可能会抛出可以捕获或 toast 的异常。伙计们需要这方面的帮助
谢谢!