File oldFile = new File("d:/dd.txt");
if(!oldFile.exists()){
oldFile.createNewFile();
}
System.out.println("修改前文件名称是:"+oldFile.getName());
String rootPath = oldFile.getParent();
System.out.println("根路径是:"+rootPath);
File newFile = new File(rootPath + File.separator + "PMSTmp");
System.out.println("修改后文件名称是:"+newFile.getName());
if (oldFile.renameTo(newFile)){
System.out.println("修改成功!");
}else{
System.out.println("修改失败");
}