文件IO的几种方式

记录：对于文件IO操作方法的，后期可以用于数据驱动测试自动化中的针对文件用例或者Excel用户参数的读取、写入执行

public class FileTest {

    /**
     * 在当前目录下创建文件
     *
     * @param fileName
     */
    public void createFile(String fileName) {
        try {
            String currentFilePath = FileTest.class.getResource("/").toURI().getPath();
            String pathFileName = currentFilePath + "\" + fileName;
            File file = new File(pathFileName);
            boolean bRet = file.createNewFile();
            if (bRet) {
                System.out.println(pathFileName + "--新文件创建成功");
            } else {
                System.out.println(pathFileName + "--新文件创建失败");
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    /**
     * 根据指定的目录，查询当前目录下的所有子目录名
     *
     * @param dirName     路径名
     * @param allFileName 所有文件的名称
     */

    public void getDirAllFileName(String dirName, List<String> allFileName) {
        if (dirName != null && allFileName != null) {
            File file = new File(dirName);
            if (file.exists()) {
                File[] files = file.listFiles();
                for (File f : files) {
                    if (f.isDirectory()) {
                        String subPath = f.getPath();             //获得子目录的文件名
                        getDirAllFileName(subPath, allFileName);      //递归
                    } else {
                        allFileName.add(dirName + "------" + f.getName());
                    }
                }
            }
        } else {
            System.out.println("入参为null");
        }
    }

    /**
     * 读取文件，返回文件对应的字节数组
     *
     * @param fileName
     * @return
     */
    public List<Byte> readFile(String fileName) {
        List<Byte> bytes = new ArrayList<Byte>(1024 * 100);
        File file = new File(fileName);
        try {
            FileInputStream fileInputStream = new FileInputStream(file);
            FileOutputStream outputStream = new FileOutputStream("F:\stream1.jpg");
            byte[] bs = new byte[1024];
            int iCount;
            while ((iCount = fileInputStream.read(bs)) != -1) {
                for (Byte bt : bs) {
                    bytes.add(bt);
                }
                outputStream.write(bs);                 //一次写一个缓冲区的数据
            }
            fileInputStream.close();    //关闭字节流
            outputStream.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
        return bytes;
    }

    /**
     * 把字节流数组写入指定的文件中
     *
     * @param bytes
     * @param pathFileName
     * @throws Exception
     */
    public void writeFile(List<Byte> bytes, String pathFileName) throws Exception {
        if (bytes != null && pathFileName != null) {
            File file = new File(pathFileName);
            try {
                FileOutputStream fileOutputStream = new FileOutputStream(file);
                byte[] bt = new byte[bytes.size()];
                for (int i = 0; i < bytes.size(); i++) {
                    bt[i] = bytes.get(i);
                }
                fileOutputStream.write(bt);
                fileOutputStream.close();
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    }

    /**
     * 读取文本文件
     *
     * @param fileName
     * @return
     */
    public String readTextFile(String fileName) {
        StringBuilder builder = new StringBuilder();
        if (fileName != null) {
            BufferedReader in = null;
            try {
                in = new BufferedReader(new FileReader(fileName));     //用缓存提高效率
                String str;
                while ((str = in.readLine()) != null) {
                    builder.append(str);
                    System.out.println(str);
                }
            } catch (Exception e) {
                e.printStackTrace();
            } finally {
                if (in != null) {
                    try {
                        in.close();
                    } catch (Exception e) {
                        e.printStackTrace();
                    }
                }
            }
        }

        return builder.toString();
    }
}

相应的测试类：

public class TestReader {
    public static void main(String[] args) {
        FileTest fileTest = new FileTest();
        String strRet = fileTest.readTextFile("F:\aa.txt");
    }
}

public class TestRecursive {
    public static void main(String[] args) {
        FileTest fileTest = new FileTest();
        String dirName = "D:\WorkSpace";
        List<String> allFileName = new ArrayList<String>(200);
        fileTest.getDirAllFileName(dirName, allFileName);
        for (String filename : allFileName) {
            System.out.println(filename);
        }
        System.out.println("一共有：" + allFileName.size() + "文件");
    }
}

public class TestStream {
    public static void main(String[] args){
        FileTest fileTest = new FileTest();
        String file  = "F:\stream.jpg";
        List<Byte> bytes =  fileTest.readFile("F:\t0132e5ce657c0702ac.jpg");
        System.out.println("文件大小："+ bytes.size());
  /*      try{
            fileTest.writeFile(bytes,file);
            System.out.println(file+"复制成功");
        }catch (Exception e){
            e.printStackTrace();
        }*/

    }
}

写了个Log类，用于不使用Log4j时的轻量化处理

public class Log {
    public static void writeError(String strSource, String errMsg) {
        PrintWriter out = null;
        try {
            String path = Log.class.getResource("/").toURI().getPath();
            String pathFileName = path + "\" + "errlog";
            File file = new File(pathFileName);
            if (!file.exists()) {
                file.createNewFile();
            }
            out = new PrintWriter(new BufferedWriter(new FileWriter(file,true)));
            SimpleDateFormat sd = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
            out.println(sd.format(new Date()));
            out.println(strSource);
            out.println(errMsg);
            out.println("");
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            if (out != null) {
                try {
                    out.close();
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        }
    }
}

相关测试：

public class TestLog {
    public static void main(String[] args){
        Log.writeError("FileTest-->>readTxtFile","数据库连接失败");
        Log.writeError("FileTest-->>writeFile","连接中断");
        Log.writeError("FileTest-->>readFile","IO错误");
    }
}