java - 在servlet中写入文件时出错

Question

我已经通过 servlet 中的 doPost 方法创建了一个文件，但无法向其中写入数据。我不明白是什么错误。顺便说一下，文件正在创建

// TODO Auto-generated method stub
        response.setContentType("text/html");
        String name=request.getParameter("name");
        response.getWriter().println(name);
        File filename= new File("/home/ksampath/D3/DedupeEngine/cache3.txt");
        filename.createNewFile();
        BufferedWriter out = null;
        try
        {
            System.out.println("I am going to create a new file");
            FileWriter fw=new FileWriter("cache3.txt",true);
            out=new BufferedWriter(fw);
            out.write("hello world");
            out.write(name);
        }

        catch(IOException e)
        {
            System.err.println("Error"+ e.getMessage());
        }
        finally
        {
            if(out!=null)
            {
                out.close();
            }
        }
        /*
        System.out.println("Lets us check whether it works");
        PrintWriter writer=response.getWriter();
        writer.println("<h3>hello This is my first servlet</h3>");*/
    }

Answer 1

尝试

FileWriter fw=new FileWriter(filename,true);   //where filename is that File object

public FileWriter(File file, boolean append) throws IOException

Constructs a FileWriter object given a File object. If the second argument is true, then bytes will be written to the end of the file rather than the beginning.

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