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Java has many tools that allow you to work with dates and times. Here we will use a Date object and SimpleDateFormat. Our task is this: the user should enter a date from the keyboard in the format "2013-08-18", and the application must convert the entered date into the format "AUG 18, 2013".

You and I both know very well which letters are vowels and which are consonants. We need to teach these concepts to intelligent robots, so we'll write a program to train them. The user will enter a string from the keyboard. Then a special method will help to split the entered data into two strings: one with all the vowels and another with only the consonants.

Once there were five classes: red riding hood, grandmother, pie, woodcutter, and wolf. Each class has 2 fields: ArrayList killed and ArrayList ate. Create the necessary objects (hood, grandmother, ...). Then arrange the relationships correctly according to who ate and/or killed who to bring to life what happened in the old Terran fairy tale "Little Red Riding Hood".

Faint steps could be heard, and then Master Yu Wu, an expert in the art of positioning objects, appeared in the room. He frowned at the code and said what the programmer was afraid to hear: "Where they are needed, the static modifiers are not. Your error herein lies". The master was correct: Rearrange the static modifiers so that the program compiles.

By Level 9, students are already adept at manipulating arrays and they know a thing or two about lists. Let's unify this knowledge by trying the following task. We'll create a list whose elements are arrays of numbers. Then we'll add to the list five array objects whose lengths are 5, 2, 4, 7, and 0, respectively. Finally, we'll fill the arrays with any data and display them on the screen.

I'd like ten cats and Java expertise, please. Preferably at the same time! Not a problem, hang on: the program has a Cat class with a String variable name. You need to create a Map and add 10 cats represented by (name, Cat) pairs. Then get a Set of all cats from the Map and display it on the screen.

A developer pensively scratching her head while reviewing code is a sign that it won't compile! You must resign yourself to such situations and not be nervous. Here's some practice: The program reads in two file names. It copies the first file to the location specified by the second file name. And yes, the program doesn't work. Fix the mistake.

Old task: Enter 2 file names, and copy the first file to the location specified by the second file name. New task: Enter 2 file names, and copy the first file to the location specified by the second file name. If the file to be copied doesn't exist, then the program reports it and reads another source file name and only then reads the destination file name.

The inhabitants of Planet Linear Chaos give their children sorting tasks instead of Rubik's cubes. Here's a pastime enjoyed by small ordered isomorphs. Knock yourself out: after the user enters a list of words (and numbers) from the keyboard, the program should display the words in ascending order, and the numbers in descending order.