如何正确处理throwIndexOutOfBoundsException？基本上，我正在查询用户。如果用户存在，则显示其个人资料。但是，如果找不到任何条目，它将使我的应用程序崩溃并引发异常。我应该在“ else”语句中添加些什么，以使应用程序不会崩溃？
@Override
public void done(List<ParseUser> parseUsers, ParseException e) {
if (e == null) {
// The query was successful.
ParseUser user = parseUsers.get(0);
String userId = user.getObjectId();
showProfileActivity(userId);
} else {
// The query was unsuccessful.
}
}
});
这是logcat：
10-14 21:27:06.888 28595-28595/com.app.social E/AndroidRuntime﹕ FATAL EXCEPTION: main
Process: com.elgami.customizer, PID: 28595
java.lang.IndexOutOfBoundsException: Invalid index 0, size is 0
at java.util.ArrayList.throwIndexOutOfBoundsException(ArrayList.java:255)
at java.util.ArrayList.get(ArrayList.java:308)
at com.elgami.feed.SearchActivity$1$1.done(SearchActivity.java:74)
at com.elgami.feed.SearchActivity$1$1.done(SearchActivity.java:67)
at com.parse.Parse$6$1.run(Parse.java:944)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:148)
at android.app.ActivityThread.main(ActivityThread.java:5417)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)
最佳答案
您可以检查列表是否为空：
@Override
public void done(List<ParseUser> parseUsers, ParseException e) {
if (!parseUsers.isEmpty()) {
// The query was successful.
ParseUser user = parseUsers.get(0);
String userId = user.getObjectId();
showProfileActivity(userId);
} else {
// The query was unsuccessful.
}
}
});
或者，如果您想捕获异常，请使用try -catch像这样：
@Override
public void done(List<ParseUser> parseUsers, ParseException e) {
if (e==null) {
// The query was successful.
try{
ParseUser user = parseUsers.get(0);
String userId = user.getObjectId();
}
catch(ArrayIndexOutOfBoundsException e)
{
// Print message for user does not exist .
}
showProfileActivity(userId);
}
else {
// The query was unsuccessful.
}
}
});