JavaIO 文件的读取,写入,复制,压缩,解压等...相干利用,持续更新 - ToB企服应用市场:ToB评测及商务社交产业平台

/**
* 逐行读取文本
*
* @param filePath 文件路径
* @return List<String>
*/
public static List<String> readTxtFile1(String filePath) throws IOException {
Path path = Paths.get(filePath);
//判断文件是否存在
if (!Files.exists(path)) {
log.error("file is not exist");
return null;
}
List<String> txtList = new ArrayList<>();
try (InputStreamReader read = new InputStreamReader(Files.newInputStream(path), StandardCharsets.UTF_8);
BufferedReader bufferedReader = new BufferedReader(read)) {
String lineTxt;
while (null != (lineTxt = bufferedReader.readLine())) {
if (StringUtils.isNotEmpty(lineTxt)) {
txtList.add(lineTxt);
}
}
}
return txtList;
}

复制代码

/**
* 以指定的编码写入数据
*/
private static void outputStreamWriter(String filePath, List<String> content, Charset charset, boolean append) throws IOException {
try (OutputStreamWriter writer = new OutputStreamWriter(new FileOutputStream(filePath, append), charset);
BufferedWriter bufferedWriter = new BufferedWriter(writer)) {
for (String item : content) {
bufferedWriter.write(item);
bufferedWriter.newLine();
}
}
}

复制代码

/**
* 简单的文件拷贝,不使用缓冲区,适用于小文件
*
* @param sourceFile 源文件
* @param targetFile 目标文件
*/
public static void copyFile(String sourceFile, String targetFile) throws IOException {
try (FileInputStream fileInputStream = new FileInputStream(sourceFile);
FileOutputStream fileOutputStream = new FileOutputStream(targetFile)) {
byte[] b = new byte[1024];
int length;
while ((length = fileInputStream.read(b)) != -1) {
fileOutputStream.write(b, 0, length);
// 不能用 fileOutputStream.write(b) 因为最后有可能读不够而出错
}
}
}

复制代码

/**
* 进行文件的拷贝-高效
* 使用字节处理流字节缓冲输入流和字节缓冲输出流
*
* @param source 源
* @param target 复制到
* @return boolean 结果
*/
public static boolean BufferedStreamFileCopy(String source, String target) {
if (StringUtils.isEmpty(source) || StringUtils.isEmpty(target)) {
log.error("文件路径不存在! path:{}", source);
return false;
}
if (source.equals(target)) {
log.error("复制的源文件和目标文件不能是同一个文件! path:{}", source);
return false;
}
Path path = Paths.get(source);
boolean exists = Files.exists(path);
if (!exists) {
log.error("文件不存在! path:{}", source);
return false;
}
long currentTimeMillis = System.currentTimeMillis();
try (BufferedInputStream bufferedInputStream = new BufferedInputStream(Files.newInputStream(path));
BufferedOutputStream bufferedOutputStream = new BufferedOutputStream(Files.newOutputStream(Paths.get(target)))) {
byte[] bytes = new byte[1024];
int length;
while ((length = bufferedInputStream.read(bytes)) != -1) {
bufferedOutputStream.write(bytes, 0, length);
}
log.info("copy file success, time:{} ms", System.currentTimeMillis() - currentTimeMillis);
return true;
} catch (IOException e) {
log.error("BufferedStreamFileCopy 拷贝文件异常", e);
return false;
}
}

复制代码

/**
* 编码转换- 如一个文件的编码是 gb2312 转为 utf-8
* 请注意,请用文件本身的正确的编码尝试读取,否则会乱码
*
* @param filePath 原始文件
* @param oldCharset 原始字符编码
* @param newFilePath 新文件
* @param newCharset 新字符编码
* @throws IOException io异常
*/
private static void conversionCharset(String filePath, String oldCharset, String newFilePath, String newCharset) throws IOException {
try (InputStreamReader reader = new InputStreamReader(Files.newInputStream(Paths.get(filePath)), oldCharset);
BufferedReader bufferedReader = new BufferedReader(reader);
OutputStreamWriter outputStreamWriter = new OutputStreamWriter(Files.newOutputStream(Paths.get(newFilePath)), newCharset);
BufferedWriter bufferedWriter = new BufferedWriter(outputStreamWriter)) {
String line;
while (null != (line = bufferedReader.readLine())) {
bufferedWriter.write(line);
bufferedWriter.newLine();
}
}
}

复制代码