读一个文件放在List中,然后想将List中的元素转化为Long型。
文件格式:
1177503586493
1177503586493
1177503586493
1177503586493
1177503586493大概代码:
fromFile(String filename){ try{
FileReader reader = new FileReader(filename);
BufferedReader buff = new BufferedReader(reader);
String line;
while ((line = buff.readLine()) != null){
list.add(line);
}
buff.close();
reader.close();
}
catch (IOException e){
System.out.println("Error --" + e.toString());
}
return list;
}pubic void Check (){ Long buffer;
List bufferlist; bufferlist = fromFile(filename);
for (ing i = 0; i < bufferlist.size(); i++ )
buffer = Long.parseLong(bufferlist.get(i))
}错误提示 cannot resolve symbol
symbol : method parseLong (java.lang.Object)但是我用bufferlist.get(i)).getClass()提示java.lang.String明明是将String类型加入List中,但是get的是object,是重载的原因吗?如何将这个List中的元素转化成String或Long类型?
先谢谢各位了:)
文件格式:
1177503586493
1177503586493
1177503586493
1177503586493
1177503586493大概代码:
fromFile(String filename){ try{
FileReader reader = new FileReader(filename);
BufferedReader buff = new BufferedReader(reader);
String line;
while ((line = buff.readLine()) != null){
list.add(line);
}
buff.close();
reader.close();
}
catch (IOException e){
System.out.println("Error --" + e.toString());
}
return list;
}pubic void Check (){ Long buffer;
List bufferlist; bufferlist = fromFile(filename);
for (ing i = 0; i < bufferlist.size(); i++ )
buffer = Long.parseLong(bufferlist.get(i))
}错误提示 cannot resolve symbol
symbol : method parseLong (java.lang.Object)但是我用bufferlist.get(i)).getClass()提示java.lang.String明明是将String类型加入List中,但是get的是object,是重载的原因吗?如何将这个List中的元素转化成String或Long类型?
先谢谢各位了:)
把这句话改成:
buffer = Long.parseLong((String)bufferlist.get(i))
这样看看
String s = (String)bufferlist.get(i);
System.out.println(s);
buffer = Long.parseLong((s));
System.out.println("number is:" + s);
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即使这样,还是要转型的.