chinabugotech/hutool · error · IORuntimeException

File not exist: {}

Error message

File not exist: {}

What it means

FileUtil.copyFile(File src, File dest, StandardCopyOption...) delegates to NIO Files.copy after preconditions. It verifies the source exists; if src does not exist it throws IORuntimeException("File not exist: {}") before attempting the OS-level copy.

Source

Thrown at hutool-core/src/main/java/cn/hutool/core/io/FileUtil.java:1137

		Assert.notNull(src, "Source File is null !");
		Assert.notNull(dest, "Destination File or directiory is null !");
		return copyFile(src, dest.toPath(), options).toFile();
	}

	/**
	 * 通过JDK7+的 Files#copy(Path, Path, CopyOption...) 方法拷贝文件
	 *
	 * @param src     源文件
	 * @param dest    目标文件或目录，如果为目录使用与源文件相同的文件名
	 * @param options {@link StandardCopyOption}
	 * @return 目标文件
	 * @throws IORuntimeException IO异常
	 */
	public static File copyFile(File src, File dest, StandardCopyOption... options) throws IORuntimeException {
		// check
		Assert.notNull(src, "Source File is null !");
		if (false == src.exists()) {
			throw new IORuntimeException("File not exist: " + src);
		}
		Assert.notNull(dest, "Destination File or directiory is null !");
		if (equals(src, dest)) {
			throw new IORuntimeException("Files '{}' and '{}' are equal", src, dest);
		}
		return copyFile(src.toPath(), dest.toPath(), options).toFile();
	}

	/**
	 * 复制文件或目录<br>
	 * 如果目标文件为目录，则将源文件以相同文件名拷贝到目标目录
	 *
	 * @param srcPath    源文件或目录
	 * @param destPath   目标文件或目录，目标不存在会自动创建（目录、文件都创建）
	 * @param isOverride 是否覆盖目标文件
	 * @return 目标目录或文件
	 * @throws IORuntimeException IO异常
	 */

View on GitHub (pinned to 8870454b2a)

Solutions

1. Verify src.exists() (or FileUtil.isFile(src)) immediately before calling copyFile.
2. Re-check the source path spelling and that it points to a generated file.
3. On failure, surface the absolute path in your own error for faster diagnosis.

Example fix

// before
FileUtil.copyFile(src, dest); // throws if src missing

// after
if (!src.exists()) {
    throw new FileNotFoundException("source missing: " + src);
}
FileUtil.copyFile(src, dest);

if (src != null && src.exists()) {
    FileUtil.copyFile(src, dest, options);
} else {
    throw new java.io.FileNotFoundException("source missing: " + src);
}

static boolean isCopyableSource(File f) {
    return f != null && f.isFile();
}

try {
    return FileUtil.copyFile(src, dest, options);
} catch (IORuntimeException e) {
    if (e.getMessage().startsWith("File not exist")) {
        // source vanished: regenerate or report
    }
    throw e;
}

When it happens

Trigger: Calling FileUtil.copyFile where the source File does not exist (deleted, wrong path, never created).

Common situations: Source path from configuration is wrong or stale; a race where src is removed between your check and the call; a typo in the source path; copying before the source is generated.

Related errors

• File not exist: {}
• Not a regular file!
• File path is blank!
• Input must be a File
• Files '{}' and '{}' are equal

AI-assisted analysis of chinabugotech/hutool@8870454b2a (2026-08-14). Data as JSON: /api/errors/bb668855e543d6fc. Report an issue: GitHub.