Slide 1Slide 2Slide 3Slide 4Slide 5Slide 6Slide 7Slide 8Slide 91Strings and Arrays2/5/20092Opening Discussion■Do you have any questions about the assignment?■What is the syntax of generics?■What are enums?■What is the syntax of Java enums?■Minute Essay commentsComparing Java to SmalltalkYou don't have to use Eclipse to program Java. There are other IDEs, like NetBeans, or oyu could use vi. API is pretty essential.Java 5 was released in September 2004.My research work uses both Java and C++.Java is created by a large team of people.Meaning of abstract.3Strings■How did you represent a string in C? How do we represent a string in Java?■Let's go look at the API for String to see what the Java developers have provided us with.■Strings are immutable so it is very inefficient to build big strings from a lot of little pieces. If you need to do that, use StringBuffer.■It is the only class with an overloaded operator, + for string concatenation.■Functions that look like they mutate the String return a new String instead.■To get a single character, use charAt.4Text/In Class Project■In class we will be going through the same project that is developed in the textbook. It is a drawing program with a somewhat different structure than paint.■In addition to drawing, the application will also have command processing that we can use to extend the power of the application.5Code■To give us a chance to play with strings some let's go ahead and write the beginnings of the command processor.■We want a class that will take a string, break off the first word as the command, then execute the command with the rest of the string as the arguments.■We should go ahead and make two commands, echo and add, that we can test it with.6Regular Expressions■You'll notice that some of the methods in String say that they take regular expressions (regex). This is a topic that we won't directly cover in this class, but it is a very powerful technique for you to learn.■The java.util.regex package contains the two main classes that are used for regular expressions. The Pattern class has a lot of description about them at the top.7Arrays■Array syntax in Java is just like it was in C as far as using the arrays. There are significant differences though.■Array types are made by putting [] after a regular type.■Array types are object types so your variables are references and should be instantiated with new.■Arrays have bounds checking and know their length.■You can't make arrays of generics.■Each element in the array is like a variable. So for primitives they store values while for object values they are references.8Code■Our command parser was pretty lame in how it picked the command. The definitely isn't a very flexible I want to write a class called ArrayMap and use it to make the code more flexible.9Minute Essay■Write the following method:String replaceAll(String s,char f,char t)■This method should return a new string where all instances of f in s have been replaced with t.■Remember to submit your design for assignment #1 today.■Interclass Problem – Write a program where a user types in a line of text and you print out each word in the line and the number of characters in
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