尝试并在java中捕获语句？

Question

如何使用try和catch语句而不是方法头中的throws子句重写以下方法:

public String getInput(String filename) throws Exception
{
    BufferedReader infile = new BufferedReader (new FileReader(filename));
    String response = infile.readLine();
    infile.close();

    return response:
}

Answer 1

Try和catch用于优雅地处理异常,而不是隐藏异常.如果你正在调用getinput(),你不想知道出了什么问题吗？如果你想隐藏它,我想你可以做类似的事情

public String getInput(String file) {
    StringBuilder ret = new StringBuilder();
    String buf;
    BufferedReader inFile = null;

    try {
        inFile = new BufferedReader(new FileReader(filename));
        while (buf = inFile.readLine())
            ret.append(buf);
    } catch (FileNotFoundException e) {
        ret.append("Couldn't find " + file);
    } catch (IOException e) {
        ret.append("There was an error reading the file.");
    } finally {
        if (inFile != null) {
           try {
              inFile.close();
           } catch (IOException aargh) {
              // TODO do something (or nothing)
           }
        }
    }

    return ret.toString();
}

值得注意的是,您希望单独捕获异常.盲目捕捉,Exception因为一些答案建议是一个坏主意.你不想抓住你从未见过的东西来处理你所做的事情.如果你想捕获你从未见过的异常​​,你需要记录它并优雅地向用户显示错误.