Please explain each line of code :-)

public class Accumulator { private double total: private int N: } public class Transaction { private final String who: private final Date when: private final double amount: } public class FixedCapacityStackOfStrings { private String [] a = new String [C]: // stack entries private int N: // size } class INode implements Comparable { protected byte [] name: protected long modificationTime: protected long accessTime: } class INodeFile extends INode { private long header: private Block [] blocks: } class INodeDirectory extends INode { private INodeFile [] children: } public class Block implements Comparable { private long blockId: private long numBytes: private long generationStamp: }