A DESCRIPTION OF THE PROBLEM :
in the documentation is mentioned that different paths could be added by comandline parameter -cp when they are split by ':' (see in documentation sdkTool -classpath classpath1:classpath2...)

this is not working. you have to use a semicolon to add different paths to the classpath

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
Synopsis
The class search path (class path) can be set using either the -classpath option when calling a JDK tool (the preferred method) or by setting the CLASSPATH environment variable. The -classpath option is preferred because you can set it individually for each application without affecting other applications and without other applications modifying its value.

sdkTool -classpath classpath1;classpath2...

set CLASSPATH=classpath1;classpath2...

sdkTool
A command-line tool, such as java, javac, javadoc, or apt. For a listing, see JDK Tools and Utilities at
http://docs.oracle.com/javase/8/docs/technotes/tools/index.html

classpath1;classpath2
Class paths to the JAR, zip or class files. Each class path should end with a file name or directory depending on what you are setting the class path to, as follows:
ACTUAL -
Synopsis
The class search path (class path) can be set using either the -classpath option when calling a JDK tool (the preferred method) or by setting the CLASSPATH environment variable. The -classpath option is preferred because you can set it individually for each application without affecting other applications and without other applications modifying its value.

sdkTool -classpath classpath1:classpath2...

set CLASSPATH=classpath1;classpath2...

sdkTool
A command-line tool, such as java, javac, javadoc, or apt. For a listing, see JDK Tools and Utilities at
http://docs.oracle.com/javase/8/docs/technotes/tools/index.html

classpath1:classpath2
Class paths to the JAR, zip or class files. Each class path should end with a file name or directory depending on what you are setting the class path to, as follows:

URL OF FAULTY DOCUMENTATION :
https://docs.oracle.com/javase/8/docs/technotes/tools/windows/classpath.html