参考:《第一行代码》
Java部分还不是很熟,渣渣在努力

在安卓的数据存储方式中有一招是文件存储,当然安卓内置有Context类的openFileOutput()方法将数据存储到指定文件中,有openFileInput()方法打开指定文件。openFileOuput()方法返回一个FileOutputStream对象,openFileInput()方法返回一个FileInputStream对象,拿到这对象以后就可以使用java流的方式将数据写入或读出文件了。

java流文件写入
openFileOutput()方法返回FileOutputStream对象,再拿到OutputStreamWriter(中间桥梁)对象,再拿到BufferedWriter(缓冲)对象,再调用write()方法写入,注意close(),

public void save(String inputText){
        FileOutputStream out=null;
        BufferedWriter writer=null;
        try {
            out=openFileOutput("data", MODE_PRIVATE);
            writer=new BufferedWriter(new OutputStreamWriter(out));
            writer.write(inputText);
        } catch (FileNotFoundException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        finally{
            if(writer!=null){
                try {
                    writer.close();
                } catch (IOException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }
            }
        }
    }

java流的文件读出(与写入对应,为加深记忆,再写一遍)
首先,openFileInput()拿到FileInputStream对象,再通过这个对象拿到InputStreamReader对象,再通过InputStreamReader对象拿到BufferedReader对象,从而调用readline()方法进行读出,不要忘了close(),

public String  load(){
        FileInputStream inputStream=null;
        BufferedReader reader=null;
        StringBuilder contentBuilder=new StringBuilder();
        try {
            inputStream=openFileInput("data");
            reader=new BufferedReader(new InputStreamReader(inputStream));
            String line="";
            while((line=reader.readLine())!=null){
                contentBuilder.append(line);
            }
        } catch (FileNotFoundException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        finally{
            if(reader!=null){
                try {
                    reader.close();
                } catch (IOException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }
            }
        }
        return contentBuilder.toString();
    }