To compile Java class: lic class Triangle { // Instance variables for 3 triangle sides private String
side1; private String side2; private String side3; // Constructors public Triangle() { // a default
triangle this("0", "0", "0"); }
public class Triangle {
// Instance variables for 3 triangle sides
private String side1;
private String side2;
private String side3;
// Constructors
public Triangle() {
// a default triangle
this("0", "0", "0");
}
public Triangle(String str1, String str2, String str3) {
this.side1 = str1;
this.side2 = str2;
this.side3 = str3;
}
// Instance methods
public String triangleType() {
String type = "";
int s1 = 0, s2 = 0, s3 = 0;
String errMessage = "";
try {
s1 = Integer.parseInt(side1);
} catch (NumberFormatException e) {
errMessage += "The side 1 is not an integer number.nn";
}
try {
s2 = Integer.parseInt(side2);
} catch (NumberFormatException e) {
errMessage += "The side 2 is not an integer number.nn";
}
try {
s3 = Integer.parseInt(side3);
} catch (NumberFormatException e) {
errMessage += "The side 3 is not an integer number.nn";
}
// Check for a negative side
if (s1 < 0 || s2 < 0 || s3 < 0) {
errMessage += "At least one side is negative!n";
}
// Check for vaide sides
if ((s1 + s2 <= s3) || (s1 + s3 <= s2) || (s2 + s3 <= s1)) {
errMessage += "Not a valid triangle!n";
}
if (s1 + s2 + s3 > 1000) {
errMessage += "This triangle is too big.n";
}
if (errMessage.length() > 0) {
type = errMessage ;
}
else {
if ((s1 == s2) && (s2 == s3)) {
type = "This is an equilateral triangle. ";
}
else if (( s1 == s2) || (s2 == s3) || (s1 == s3)) {
type = "This is an isosceles triangle. ";
}
else {
type = "This is a scalene triangle. ";
}
}
return type;
}
}
To compile Java class: javac Triangle.java
To compile JUnit test: javac -cp junit.jar;. TriangleTest.java
To run JUnit test: java -cp junit.jar;hamcrest-core.jar;. org.junit.runner.JUnitCore TriangleTest.
