Linux centOS shell to determine whether files and folders exist

The shell judges whether the file, directory exists or has permissions 
  #!/bin/sh 
 
myPath="/var/log/httpd/" 
myFile="/var /log/httpd/access.log" #The 
 
-x parameter here judges $myPath Whether it exists and has executable permission 
if [ ! -x "$myPath"]; then 
mkdir "$myPath" 
fi  #The


-d parameter here determines whether $myPath exists, ! -d means it does not exist
if [ ! -d " $myPath"]; then 
mkdir "$myPath" 
fi  #The
 
-f parameter here determines whether $myFile exists 
if [ ! -f "$myFile" ]; then 
touch "$myFile" 
fi  #Other
 
parameters are -n,- n is to determine whether a variable has a value 
if [ ! -n "$myVar" ]; then 
echo "$myVar is empty" 
exit 0 
fi #Two 
 
variables to determine whether they are equal 
if [ "$var1" = "  $var2" ]; then 
echo '$var1 eq $var2' 
else 
echo '$var1 not eq $var2' 
fi