java读取文件内容到变量和把变量的内容存储到文件

1.将字符串变量中的内容存储到文件中的函数：

/**
	    * 把字符串写入文本中
	    * @param fileName 生成的文件绝对路径
	    * @param content 文件要保存的内容
	    * @param enc  文件编码
	    * @return
	    */
	    public static boolean writeStringToFile(String fileName,String content,String enc) {
	        File file = new File(fileName);
	        try {
	            if(file.isFile()){
	                file.deleteOnExit();
	                file = new File(file.getAbsolutePath());
	            }
	            OutputStreamWriter os = null;
	            if(enc==null||enc.length()==0){
	                os = new OutputStreamWriter(new FileOutputStream(file));
	            }else{
	                os = new OutputStreamWriter(new FileOutputStream(file),enc);
	            }
	            os.write(content);
	            os.close();
	        } catch (Exception e) {
	            e.printStackTrace();
	            return false;
	        }
	        return true;
	    }

 

2.将文件的内容转换成字符串

/**
	 * 将文件内容转换成字符串
	 * @param filePath
	 * @return
	 * @throws IOException
	 */
	public static String loadFileToString(String filePath) throws IOException {
        BufferedReader br = null;
        String ret = null;
        File file = new File(filePath);
        try {
        	br = new BufferedReader(new InputStreamReader(new FileInputStream(filePath), "UTF-8"));
            String line = null;
            StringBuffer sb = new StringBuffer((int)file.length());
            while( (line = br.readLine() ) != null ) {
                sb.append(line);
            }
            ret = sb.toString();
        } finally {
            if(br!=null) {try{br.close();} catch(Exception e){} }
        }
        return ret;        
    }

 注：上述两个函数中的参数fileName和filePath其实都需要给出file文件的绝对路径