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copied!<p>I highly suggest reading through the <a href="http://docs.oracle.com/javase/tutorial/java/javaOO/classes.html" rel="nofollow">Java tutorial on classes and objects</a>, which will give you a good basis to work from.</p> <p>The most basic way to pass data between classes is to define public methods in your class that other objects can call to get access to your data. For example:</p> <pre><code>public class Person { private String firstName; private String lastName; public String getFirstName () { return firstName; } public String getLastName () { return lastName; } } </code></pre> <p>Methods with names like <code>getX()</code> that return values are called "getters". Then, in another class, you can access that data, for example:</p> <pre><code>public void elsewhere () { Person p = new Person(); System.out.println(p.getFirstName() + " " + p.getLastName()); } </code></pre> <p>Another way to communicate with classes is to write methods that take parameters, e.g.:</p> <pre><code>public void printFullName (Person p) { System.out.println(p.getFirstName() + " " + p.getLastName()); } public void elsewhere () { Person p = new Person(); printFullName(p); } </code></pre> <p>You may also want to provide methods to <em>set</em> data in an object. These are called "setters" and are the counterpart to "getters". Building on <code>Person</code> from above:</p> <pre><code>public class Person { private String firstName; private String lastName; public String getFirstName () { return firstName; } public String getLastName () { return lastName; } public void setFirstName (String firstName) { this.firstName = firstName; } public void setLastName (String lastName) { this.lastName = lastName; } } </code></pre> <p>Then, other objects can modify a person's data, e.g.:</p> <pre><code>public void elsewhere () { Person p = new Person(); p.setFirstName("Bob"); System.out.println(p.getFirstName()); // prints "Bob" } </code></pre> <p>Here's an example using everything from above:</p> <pre><code>public void swapPersonFirstAndLastName (Person p) { String temporary = p.getFirstName(); p.setFirstName(p.getLastName()); p.setLastName(temporary); } public void printFullName (Person p) { System.out.println(p.getFirstName() + " " + p.getLastName()); } public void example () { Person p = new Person(); p.setFirstName("John"); p.setLastName("Smith"); swapPersonFirstAndLastName(p); printFullName(p); // prints Smith John } </code></pre> <p>Hope that helps and good luck. Read those tutorials!</p>

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