I need help writing a code for this padlock.

1. Create a new Eclipse project and within it create a package hw2.Create the Padlockclass in the hw1package and put in stubs for all the required methods, the constructor, and the required constant. Remember that everything listed is declared public. For methods that are required to return a value, just put in a "dummy" return statement that returns zero. There should be no compile errors.You should be ableto run the sample main classSimpleTest.java.2.Briefly javadoc the class, constructorand methods. This is a required part of the assignmentanyway, and doing it now will help clarify for you what each method is supposed to do before you begin the actual implementation. (Copying from the method descriptions here or in the Javadoc is perfectly acceptable; however,DO NOT COPYAND PASTE DIRECTLY from the pdf or online Javadoc!This leads to insidiousbugscaused by invisible characters that are sometimes generated by sophisticated document formats.If you are super lazy about typing, it should be ok if you copy, paste into a dumb text editor like Notepad, and then copy/paste from there.)3.You could start by first making sure you can set and get the current rotation of each disc. According to the constructor,assuming that the tooth width is 2 degrees,the initial positionof the discs is always 0degreesfor disc 3, 2degreesfor disc 2, and 4degrees for disc 1.(Thisis true regardless of the constructor arguments.). So you should be ableto set upa simple test class with the following:Padlock p = new Padlock(10, 20, 30);printPositions(p); // expected 420p.setPositions(42, 137, 17); // order is disc 1, 2, 3printPositions(p); // expected 42 137 17

where printPositionsis a helper method that just usesthe getDiscPositionmethod to display thethree angles:private static void printPositions(Padlock p){int c = p.getDiscPosition(3);int b = p.getDiscPosition(2);int a = p.getDiscPosition(1);System.out.println(a + " " + b + " " + c);// backto front (1, 2, 3)}This would also be a good time to make sure you can normalize the anglesso they are always between 0 and 359, for example:p.setPositions(-90, 800, 42);printPositions(p); // expected 270 80 42(Tip: the sample code shown above can be foundin the given file SimpleTest.java)3. At this point you could either continueworking on disc rotations, or implement the lock logic; thetwotaskscan be tackled independently. Supposewe do lock logic first. The key piece is determining whether the discs are "aligned", as specified in the isAlignedmethod. For that we need to knowthe offsetfor each disc, that is, the angle of rotation that will put its notch inthe right position for the lock to open. According to thegeneral description of the lock internals, if the combination is 10, 20, 30, then the offsets are 6, 22, and 30, for discs 1, 2, and 3,respectively.The isAlignedmethod should return true if the current positionsofallthree discsmatchtheir offsets.So, the behavior we expect is something like this(according to the constructor, the lock should initially be open):System.out.println(p.isOpen()); // expected trueSystem.out.println(p.isAligned()); // expected falsep.close();System.out.println(p.isOpen()); // expected falsep.open();// doesnothing; it's lockedSystem.out.println(p.isOpen()); // expected falsep.setPositions(6, 22, 30); printPositions(p); // expected 6, 22, 30System.out.println(p.isAligned()); // expected true// now we should be able to open it!p.open();System.out.println(p.isOpen()); // expected trueSystem.out.println();

4. To start thinking about what happens when you rotate the dial, first think about just disc 3, the front one that is attached to the dial. You could start by just making sure you can get disc 3 to end up in the correct position:p.setPositions(4, 2, 0);p.turn(10);// 10 degrees ccwSystem.out.println(p.getDiscPosition(3)); // expected 10p.turn(-100);//100 degrees cw System.out.println(p.getDiscPosition(3)); // expected 270p.turn(800);System.out.println(p.getDiscPosition(3)); // expected 350System.out.println();5. Now it gets interesting. How does disc 3 affect disc 2? Suppose disc3 is at 30 degrees and disc 2 is at 90 degrees, and we rotate disc 3counterclockwise(ccw)70degrees. p.setPositions(0, 90, 30); p.turn(70);printPositions(p); // expected 0 102 100Here,(disc 2position) (disc3 position) = 90 30 = 60degrees, the counterclockwise rotation from disc 3 to disc 2.There is also the tooth width to account for, so disc 3 can rotate 58 degrees before it starts pushing disc 2. We're rotating disc 3 a total of 70 degreesccw, so disc 2 will be pushed 12 degrees ccw, ending up at position 102.

Maybe we should try one where the subtraction comes out negative:p.setPositions(0, 20, 350);p.turn(50); printPositions(p); // expected 0 42 40Inthis case, (disc 2position) (disc3 position) = -330degrees, which normalizes to 30 degrees. With the tooth width, disc 3 can rotate 28 degrees ccw before affecting disc 2.We're rotating 50 degrees, so disc 2 is pushed 22 degrees.6. Then try going clockwise:p.setPositions(0, 350, 20);p.turn(-40); printPositions(p); // expected 0 338340Here,(disc 2position) (disc3 position) = 330degrees,but we want the complementof this angle since we're rotatingthe opposite direction, which is 30 degrees. (Equivalently, just perform thesubtraction in the opposite orderand normalize.)Less the tooth width that's 28 degrees. Disc 3 is rotating a totalof 40 degrees clockwise (cw),so disc 2 will move12 degrees cw.New disc 3 position = 20 40 = -20, which normalizes to 340.New disc 2 position = 350 12 = 338.

Try another one:p.setPositions(45, 40, 30); p.turn(-400); printPositions(p); // expected 45 348 350Here,(disc 2position) (disc3 position) = 10degrees,but we want the complementof this angle since we're rotatingthe opposite direction, which is 350degrees;less the tooth width that's 348 degrees.Disc 1 is rotating 400 degrees cw, so disc 2 will be pushed 52 degrees.New disc 3 position = 30 400= -370, which normalizes to 350.New disc 2 position = 4052 = -12, which normalizes to 348.Accounting for theeffect of disc 2 on disc 1 is similar.In the test case above, for example, we can tell that the difference,(disc 1position) (disc2position) = 45-40 = 5 degrees, the complement of which is 355, less the tooth width is 353;but disc 2 is only rotating 52 degrees cw, so disc 1 is unaffected. If we instead hadthe same example but with disc 1 at 10 degrees:p.setPositions(10, 40, 30); p.turn(-400); printPositions(p); // expected 346 348 350Now,(disc 1position) (disc2 position) = -30degrees, normalized to 330,but we want the complement which is 30, and allowing for the tooth width,we get 28 degrees cw from disc 2 to disc 1. Disc 2 is moving 52 degrees cw as in previousexample, so disc 1 will be pushed 24 degreescw. New disc 1 position is 10 24 = -14 or 346 degrees.7. Once turnisimplemented, itis easyto implement the methods turnLeftToand turnRightTo. After that, you should be ableto open the lockaccording the instructions on the package(recall we originally constructed a padlock with combination 10, 20, 30):p.turn(-720); // spin it twice clockwisep.turnRightTo(10);p.turn(360 -Padlock.TOOTH); // counterclockwisea full revolutionp.turnLeftTo(20);p.turnRightTo(30);System.out.println(p.isAligned()); // expected truep.open();System.out.println(p.isOpen()); // hooray