Dockerfile

FROM java:8
#WORKDIR dat100-testassignment/src/hib/dat100/testassignment
#RUN javac dat100-testassignment/src/hib/dat100/testassignment/A.java 

#Must have COPY and WORKDIR in order to build successfully
#The main purpose of a CMD is to provide defaults for an executing container.
COPY . /usr/src/test 
WORKDIR /usr/src/test 
#RUN javac dat100-testassignment/src/hib/dat100/testassignment/A.java
RUN javac -cp .:junit/junit-4.12.jar:junit/hamcrest-core-1.3.jar dat100-testassignment/src/hib/dat100/testassignment/*.java
#CMD ["java","-cp", ".:junit/junit-4.12.jar:junit/hamcrest-core-1.3.jar:dat100-testassignment/src", "org.junit.runner.JUnitCore", "hib.dat100.testassignment.TestA"]     
CMD ["java","-cp", ".:junit/junit-4.12.jar:junit/hamcrest-core-1.3.jar:dat100-testassignment/src", "hib.dat100.testassignment.TestRunner"]

#FROM:
#The FROM instruction sets the Base Image for subsequent instructions. 
#As such, a valid Dockerfile must have FROM as its first instruction. 
#The image can be any valid image – it is especially easy to start by pulling an image from the Public Repositories.
#FROM must be the first non-comment instruction in the Dockerfile.
#FROM can appear multiple times within a single Dockerfile in order to create multiple images. Simply make a note of the last image ID output by the commit before each new FROM command.
#The tag or digest values are optional. If you omit either of them, the builder assumes a latest by default. The builder returns an error if it cannot match the tag value.
#FROM forms:
#1.FROM <image>
#2.FROM <image>:<tag>
#3.FROM <image>@<digest>

#COPY:
#The COPY instruction copies new files or directories from <src> and adds them to the filesystem of the container at the path <dest>.
#COPY forms:
#1. COPY <src>... <dest>
#2. COPY ["<src>",... "<dest>"] (this form is required for paths containing whitespace)
#More detials from Reference: https://docs.docker.com/engine/reference/builder/#copy

#WORKDIR:
#The WORKDIR instruction sets the working directory for any RUN, CMD, ENTRYPOINT, COPY and ADD instructions that follow it in the Dockerfile. 
#If the WORKDIR doesn’t exist, it will be created even if its not used in any subsequent Dockerfile instruction.
#WORKDIR form: 
#WORKDIR /path/to/workdir
#More detials from Reference: https://docs.docker.com/engine/reference/builder/#workdir

#NOTE:
#Don’t confuse RUN with CMD. RUN actually runs a command and commits the result; 
#CMD does not execute anything at build time, but specifies the intended command for the image.