I am writing a program that will generate a geometry Logic Word Problem, and I am having trouble with it. My goal is to have the program randomly create a word problem that is pre-designed. So far, the program takes input from the user, and then uses that information in the Story methods, somewhat like a game of Mad Libs. Anyways, I want to randomly chose a Story method to run each time the user starts the program. So far this is what I have:
import cs1.Keyboard;
public class LogicProof {
//Main method
public void main () {
System.out.println ("Enter 1. to start.");
System.out.println ("Enter 2. to exit.");
int choice = Keyboard.readInt();
if (choice == 1) { //Take info in and send to createStory
//Randomly run methods
}
if (choice == 2) {
System.out.println ("\nGoodbye.");
}
//Create the first story using inputs from main
private void createStory(String adj,String adj2,String adj3,String action) {
//Use values from main() to create a problem
}
There are two other createStory methods as well. Also, I am going to display the proofs of each problem, and each method has its own proof, so would I be able to then display the proof for the same method, basically just link together the proof method, and story method?
I'm fairly new to Java, and appreciate the help.
Thanks in advance.
To only answer your title, you could use random generation with reflection, but that is in no way how you should solve your current problem.
Don't try and randomly invoke methods. Take a look at java.util.Random's nextInt() and use that to do unique operations based on the value it returns.
This seems like Homework which is why I'm not giving you a full solution here.
public class MadLibs {
public static final String[] STARTERS = { /* ... */ };
public static final String[] ENDINGS = { /* ... */ };
public static String generate(String ... adjectives) {
final Random random = new Random();
final StringBuilder string = new StringBuilder(STARTERS[random.nextInt(STARTERS.length-1)]);
for (String adjective : adjectives) {
string.append(adjective);
string.append(TRANSITIONS[random.nextInt(TRANSITIONS.length - 1)]);
}
return string.toString();
}
}
That's an extremely simple and rough implementation to get you started.
Or maybe, if you have only a few concrete variations:
public class MadLibs {
public static String generate(String ... adjectives) {
int result = new Random().nextInt(MAX);
String madLib = null;
switch (result) {
case 0:
// ...
break;
case 1:
// ...
break;
default:
// ...
break;
}
return madLib;
}
}
Like said above, use random number generation to yourself a 1,2,3,4 ect... Then pass that number into your method as a parameter and then use "if, if else" statements to choose the correct operation to perform. Again, like stated above I will not give any code in case this is indeed a homework problem.
You could generate a Word or Phrase object, populate them into a List.
From there us something like Random or Math.random to pull a word or phrase from the list
Related
I am attempting to write a program which asks users what their pet name is, species, finds out thirst level and gives a response accordingly.
I would appreciate if someone could help me with a problem im having, in each of the 2 methods askpetname and thirstlevel there are 2 strings i want accessible throughout the entire class without using global variables.
Can someone tell me what it is i am doing incorrectly or point me in the right direction.
Also, i understand that my excess use of methods for tedious tasks is bad practice but it helps with memorising syntax.
Thanks.
class dinoo
{
public static void main(String[] p)
{
explain();
output();
System.exit(0);
}
public static void explain()
{
print("The following program demonstrates use of user input by asking for pet name.");
return;
}
public static String askpetname()
{
Scanner scanner = new Scanner(System.in);
print("Name your dinosaur pet!");
String petname = scanner.nextLine();
print("Awesome, cool dinosaur name, what species is " + petname+ " ?");
String petspecies = scanner.nextLine();
return petname, petspecies;
}
public static int thirstlevel()
{
Random ran = new Random();
int thirst = ran.nextInt(11);
int hunger = ran.nextInt(11);
return thirst,hunger;
}
public static String anger(int thirst, int hunger)
{
double angerscore = (thirst+hunger)/2;
String temper;
if(angerscore<=2)
{
temper = "Serene";
}
else if(3<=angerscore<=6)
{
temper= "Grouchy";
}
else if(6<angerscore)
{
temper = "DANGEROUS";
}
return temper;
}
public static String warning()
{
if (temper.equals("Serene"))
{
print("He's looking happy!");
}
else if(temper.equals("Grouchy"))
{
print("Ahhh hes a bit "+temper+", you better start feeding him before he gets mad!");
}
else if(temper.equals("DANGEROUS"))
{
print("GET OUT OF THERE, HES " + temper+"!!!. He will have to be put down for everyones safety.");
}
}
public static void output()
{
print(askpetname() + "'s, thirst level is "+thirstlevel()+"/10");
return;
}
public static String print(String message)
{
System.out.println(message);
return message;
}
}
That code won't compile since you can't have:
return string1, string2;
or
else if(3<=angerscore<=6)
Instead of trying to return multiple Strings, your best bet is to create a class, say called Pet, one that holds String fields for the pet's name, a Species field for its species, as well as any other fields for hunger, thirst ... that would best encapsulate all the data that makes up one logical "pet" as well as a methods such as getAnger() that returns a value for anger depending on the Pet's state. Then you can create and return a viable Pet object from your creational method.
Also, your code has lots of compilation errors, suggesting that you could improve the way that you create your code. Never try to add new code to "bad" code, to code that won't compile. If possible, use an IDE such as NetBeans, Eclipse, or IntelliJ to help you create your programs. The IDE's will flag you if any of your code contains compilation errors, and then the key is: don't add new code until you've first fixed the existing compilation error. If you can't use an IDE, then you must compile early and often, and do the same thing -- fix all errors before adding new.
First, I would recommend shooting through a tutorial first before attempting this, do all the hello worlds covering scope, objects, arrays and functions. Get familiar with Object Oriented Style, although thats not even procedural programming ... nothing returns 2 objects ... always 1 (it could be an array containing many objects, but an array is a single object)
Moving on,although this is terrible coding practice, but its ok for a beginner,since your functions are all static, create a private static variable inside each function and create getter functions
//convert
String petname = scanner.nextLine();
// To this
private static String petname = scanner.nextLine();
// Then add this below it
public static String getPetName()
{
return petname;
}
and same for every piece of data you need.
Now remove the return statement from all of your functions and declare return type as void
Then call all functions from Main,
askpetname();
thirstlevel();
then print final output (after you have called the functions) as such
System.out.println("Petname: " + getPetname + " ThirstLevel: " + getThirstLevel() + " HungerLevel: " + getHungerLevel);
I know this has been asked before, but not in a way I understood, because I am dumb.
So.
I need to take some variables into a class, compare them against something, and then return the higher of the two. In the long run, I need to compare against a running total, but for my problem, I think the issue is considerably more fundamental. I'm not understanding how to pass a variable BACK to my main class.
import java.io.*;
public class testing123 {
public static void main(String[] args) {
InputStreamReader input = new InputStreamReader(System.in);
BufferedReader reader = new BufferedReader(input);
Integer a;
Integer b;
Integer numbersCombined;
try {
System.out.println("Please enter a number");
a = Integer.parseInt(reader.readLine());
System.out.println("Please enter a number");
b = Integer.parseInt(reader.readLine());
numbersCombined = (a + b);
testClass Check = new testClass();
System.out.println("Your numbers combined is " +numbersCombined);
System.out.println(Check);
} catch (IOException e){
System.out.println("Error reading from user");
}
}
}
class testClass {
public static Integer testClass (Integer numbersCombined) {
if (numbersCombined > 100) {
numbersCombined = numbersCombined;
}
else {
numbersCombined = 100;
}
System.out.println(numbersCombined);
return numbersCombined;
}
}
If I remove the return, this will print the numbersCombined, but that's all it does. With the return in place, it doesn't execute the print line above the return, and first prints the original numbersCombined (which it shouldn't if you use, say, 10 and 20, since that's less than 100), and then prints testClass#76046e53 rather than the actual value. I know there's a way to override it, but the answers I've found don't work for me.
I know this answer: http://www.google.com/url?q=http%3A%2F%2Fstackoverflow.com%2Fquestions%2F29140402%2Fhow-do-i-print-my-java-object-without-getting-sometype2f92e0f4&sa=D&sntz=1&usg=AFQjCNGIzxlBSH8xIS7hurKe6_Euc7B8RQ
is the basic problem I'm encountering, but the overrides listed aren't really working for me, and I want integer anyway, rather than string.
In the end, what I'm "really" doing is taking a series of 4 numbers from a user, then using this function to compare whether THIS series of numbers is higher than the previous maximum, and if it is, that's the new maximum moving forward, with a loop until the user is done entering serieses of 4 numbers, and then finally printing the maximum.
I was able to write this without ANY functions, all inline, easy as pie. But once I send the comparison to a function, I don't understand how to send it back, and I've spent all day trying to understand the concept. ALL DAY. So, while I know it's going to be a stupid answer, that's because I'm stupid, but not because I didn't try (sorry, kind of defensive. Frustrated).
Fundamentally, I want to send two (this example is just one) variables to a class, compare them, change ONE of them, and return it to the main class. In this example, I'm just trying to send ONE variable, compare it, and the send it back.
You need to call the method within TestClass. Your code is already returning an integer from that method.
Once you instantiate the class run testClass.testClass(numbers)
The way you're throwing around pseudo-global variables between classes is probably the problem. Pass them through the calls like above, rather than implicitly.
Try to do something like this:
import java.io.*;
public class HelloWorld{
public static void main(String []args){
InputStreamReader input = new InputStreamReader(System.in);
BufferedReader reader = new BufferedReader(input);
Integer a;
Integer b;
Integer numbersCombined;
try {
System.out.println("Please enter a number");
a = Integer.parseInt(reader.readLine());
System.out.println("Please enter a number");
b = Integer.parseInt(reader.readLine());
numbersCombined = (a + b);
testClass Check = new testClass(numbersCombined); // constructor should be like this
System.out.println("Your numbers combined is " + numbersCombined);
System.out.println(Check);
} catch (IOException e){
System.out.println("Error reading from user");
}
}
}
class testClass {
Integer numbersCombined;
// This is a constructor
public testClass (Integer numbersCombined) {
if (numbersCombined > 100) {
this.numbersCombined = numbersCombined; // use this to represent the object
} else {
this.numbersCombined = 100;
}
System.out.println(numbersCombined);
}
// Add method toString()
public String toString() {
return this.numbersCombined.toString();
}
}
I am having an issue with a java program that I have to make for class. I am to take two letters and convert those to a location. I am to then take a message and encrypt it using a basic character swap. I seem to be having an issue with the fact that a call in my Driver file can't see the method I am trying to call in my Actions file. I sure I am missing something simple and doing it wrong but the more I read the documentation the more confused I become. Could someone please explain to me what I am doing wrong. I am trying to call my getCountry method which is in my Actions file from my Driver file. The error is at the line
locH = loc.getCountry(locationLetters);
Driver.java
/**
Program Name: Action
Date:4/14/2016
Program Description: This program is going to handle the window where the user enters data.
It is also going to be what is going to call the methods of the Actions class
Methods: Driver(),
*/
import javax.swing.*; // For the Swing classes
import java.awt.event.*; // For the ActionListener Interface
import java.util.Scanner; //for the keyboard
public class Driver extends JFrame
{
//delcare
private String locationLetters; //this is going hold the users letter selection
private String message; //this is going to hold the users message
private String locH; //for the holder of location selection
private String messH; //to hold the message before change it to an array
Scanner keyboard = new Scanner (System.in);//to make the keyboard
/**
This method is the constuctor that is going to make the window for the program to use.
*/
public Driver()
{
System.out.println("sup nerd");
yourmom();
}//end of Driver()
public String yourmom()
{
System.out.println("Please entner the two charater key for the location you want to message");
locationLetters = keyboard.next();
System.out.println("Please enter the message you would like to have encrypted.");
message = keyboard.next();
locH = loc.getCountry(locationLetters);
return locH;
}//end of yourmom()
public static void main(String[] arg)
{
Actions loc = new Actions();
Actions mess = new Actions();
new Driver();
}//end of main
}//end of Driver class
Actions.java
/**
Program Name: Action
Date:4/14/2016
Program Description: This program is going to handle all the encryption actions as well
loction where the message is being sent.
Methods:Location(),
*/
public class Actions
{
//decare
public String messE; //this is for the message that is going to be ecrypted
public String getCountry(String locHA)
{
locHA.toUpperCase();
if(locHA == "FR")
locHA = "France";
if(locHA == "GB")
locHA = "Great Britain";
if(locHA == "CA")
locHA = "Canada";
if(locHA == "JA")
locHA = "Japan";
if(locHA == "RU")
locHA = "Russia";
if(locHA == "GE")
locHA = "Germany";
if(locHA == "AU")
locHA = "Australia";
if(locHA == "MX")
locHA = "Mexico";
return locHA;
}
}//end of action class
I know that this could be done in one file but my teacher wants it in two. I know I am missing something simple but I do not understand the documentation that I have been reading in regards to using objects. Could you please point out what I have done wrong? I would be quite grateful. Thank you.
Change your main so that you pass the important data into Driver:
public static void main(String[] arg) {
Actions loc = new Actions();
Actions mess = new Actions();
new Driver(loc, mess);
}
Then use those Actions inside of the main constructor:
public Driver(Actions loc, Actions mess) {
// use parameters to set fields so that the parameter references can be
// used elsewhere in the class
this.loc = loc;
this.mess = mess;
System.out.println("sup nerd");
yourmom(loc); // and pass references where needed
}
And similarly then use the loc reference inside of the yourmom() method
Also, don't compare Strings using == or !=. Use the equals(...) or the equalsIgnoreCase(...) method instead. Understand that == checks if the two object references are the same which is not what you're interested in. The methods on the other hand check if the two Strings have the same characters in the same order, and that's what matters here. So instead of
if(locHA == "FR")
locHA = "France";
do
// always use curly braces too!
if("FR".equals(locHA)) {
locHA = "France";
}
or
// if you want to allow more liberal capitalization
if("FR".equalsIgnoreCase(locHA)) {
locHA = "France";
}
Put
Actions.getCountry();
in your main class.
And you can take the public out of the second class as it is not as easily accessible.
In Java, where should I aim (I enjoy figuring it out myself) to get, with sample data:
I am Sam I am a
the output:
I am Sam I am - letter to remove a
I m Sm I m
Basically, it is to "Remove all instances of the specified removal letter from the original sentence"
As this is for a class, I am limited with what I can do. For this assignment I am stuck with the given classes/constructors and am not allowed to make any more unless it is noted, which in my case, is to create another constructor class; Anyway, that has been the real challenge as it is hard to get help (No matter how many times I've googled!) with it being so specific and I new to the language.
Here is what I was given:
import static java.lang.System.*;
public class LetterRemover
{
private String sentence;
private char lookFor;
public LetterRemover()
{
//call set
}
//add in second constructor
public void setRemover(String s, char rem)
{
sentence = s;
lookFor = rem;
}
public String removeLetters()
{
String cleaned=sentence;
return cleaned;
}
public String toString()
{
return sentence + " - letter to remove " + lookFor;
}
}
This is what I've done so far:
import java.util.Scanner;
import static java.lang.System.*;
public class LetterRemover
{
private String sentence;
private String lookFor;
public LetterRemover()
{
//I am not sure what this means
}
//add in second constructor
public void setRemover(String s, String rem)
{
sentence = s;
lookFor = rem;
}
public String removeLetters()
{
sentence = sentence.replaceAll(lookFor,"");
String cleaned=sentence;
return cleaned;
}
public String toString()
{
return sentence + " - letter to remove " + lookFor;
}
}
I tried changing the char to a string for the "lookfor" to use the replace all method which seemed after a lot of research and the best way to get the letters out.
Is there any noticeable mistakes and where should I look to fix them? I do not really want the right code, or for anyone to "do" the work for me. I really want to try and figure it out. But I need a little help in pointing in the right direction to get my desired output :)
Let me know if there is any other details or whatnot, this is also , this is also my first time using the site. There were many similar questions to this, but as I really am a beginner I struggled to understand people's explanations
--Edit--
Moving to my runner class, this is what I wrote, trying to get for the desired output. I am not really sure how to deal with output as I really have just started learning to write them myself.
I keep getting a void error though:
import static java.lang.System.*;
public class LetterRemoverRunner
{
public static void main( String args[] )
{
LetterRemover test = new LetterRemover
(test.setRemover("I really want dumplings","l"));
}
}
Try the below code and confirm this is what your requirement is.
LetterRemoverRunner.java
public class LetterRemoverRunner {
public static void main(String args[])
{
LetterRemover test = new LetterRemover ();
test.setRemover("I really want dumplings","l");
System.out.println(test.toString());
System.out.println("Removed :"+test.removeLetters());
}
}
LetterRemover.java
public class LetterRemover
{
private String sentence;
private String lookFor;
public LetterRemover()
{
//I am not sure what this means
}
public void setRemover(String s, String rem)
{
this.sentence = s;
this.lookFor = rem;
}
public String removeLetters()
{
sentence = sentence.replaceAll(lookFor,"");
String cleaned=sentence;
return cleaned;
}
public String toString()
{
return sentence + " - letter to remove " + lookFor;
}
}
I'm pleased you suggested you don't want the answer - much better way to learn!
I'm not sure you've understood constructors yet. You're line:
LetterRemover test = new LetterRemover
(test.setRemover("I really want dumplings","l"));
Is going to give you a null pointer error because it's calling setRemover on test before test has been constructed. You should be constructing the object with its sentence and lookFor values before calling setRemover.
Here are some things you might want to look at:
The String.indexOf method will look for a certain character or string and tell you where to find it (or if it isn't in the string at all).
The String.substring method allows you to take part of a string using string positions
You can build a new string by concatenating substrings together
Using a while loop you can continue using indexOf until the target cannot be found.
As you've pointed out, you can also use one of the replace methods to replace the target with "".
I'm making a quiz like game. I have two arrays (One with the states and the other with the capitals). Basically it asks the user what capital goes with a random state. I want that if the user inputs the correct state for it to be like nice job or whatever but I do not know how to compare the user input to the specific array compartment. I tried .contains but no avail...
Any help?
My bad - I'm using Java
For Example
if(guess.equals(capitals[random]))
where guess is the string and capitals is the array and random is the random number
Basically you want a mapping String -> String (State -> Capital). This could be done using a Map<String, String> or by creating a State class which will contains its name and its capital as attributes.
But to my mind, the best option is to use an enum as you know that there is 50 states. Here's a small example.
public class Test {
static final State[] states = State.values();
static Random r = new Random();
static Scanner sc = new Scanner(System.in);
public static void main (String[] args){
State random = states[r.nextInt(states.length)];
random.askQuestion();
String answer = sc.nextLine();
if(answer.equals(random.getCapital())){
System.out.println("Congrats");
} else {
System.out.println("Not really");
}
}
}
enum State {
//Some states, add the other ones
ALABAMA("Montgomery"),
ALASKA("Juneau");
private final String capital;
private State(String capital){
this.capital = capital;
}
public String getCapital(){
return this.capital;
}
public void askQuestion(){
System.out.println("What capital goes with "+this.name()+"?");
}
}
Logic similar to this should work. You want to save the user input to a String variable, and then compare it to an n sized array.
for(int i=0; i<arrayName.length();i++)
{
if(userinputString.equalsIgnorCase(arrayName[i])
{
System.out.println("HUrray!");
}//end if
}//end for
Ok so you are somehow producing a random number, and then need to compare the input to the String in the capital Array for that random number/
Im assuming the arrays are ordered such that capitals[10] gives you the capital for states[10].
If so, just save the index to a variable.
int ranNum=RandomNumFunction();
Then just see if
if(capitals[ranNum].equalsIgnoreCase(userInput))
//do something