android读写文本文件,Android写入日志到文本文件

我正在尝试写入日志到Android文件自定义Log.txt文件使用Mine的代码，但然后此方法创建文件，但不包含任何内容。基本上我想读取文件的以前的内容，然后附加我的数据与现有的内容。

守则如下：

public static void write(String str)

{

InputStream fileInputStream = null;

FileOutputStream fileOutpurStream = null;

try

{

fileInputStream = new FileInputStream(file);

fileOutpurStream = new FileOutputStream(file);

if(file.exists())

{

int ch = 0;

int current = 0;

StringBuffer buffer = new StringBuffer();

while((ch = fileInputStream.read()) != -1)

{

buffer.append((char) ch);

current++;

}

byte data[]=new byte[(int)file.length()];

fileInputStream.read(data);

fileOutpurStream.write(data);

fileOutpurStream.write(str.getBytes(),0,str.getBytes().length);

fileOutpurStream.flush();

}

else

{

file.createNewFile();

fileOutpurStream.write(str.getBytes(),0,str.getBytes().length);

fileOutpurStream.flush();

}

}

catch(Exception e)

{

e.printStackTrace();

}

finally

{

try

{

fileInputStream.close();

fileOutpurStream.flush();

fileOutpurStream.close();

fileOutpurStream = null;

fileInputStream = null;

}

catch (IOException e)

{

// TODO Auto-generated catch block

e.printStackTrace();

}

}