8 files changed, 64 insertions, 0 deletions
diff --git a/java/01-helloworld/.gitignore b/java/01-helloworld/.gitignore
new file mode 100644
index 0000000..6b468b6
--- /dev/null
+++ b/java/01-helloworld/.gitignore
@@ -0,0 +1 @@
+*.class
diff --git a/java/01-helloworld/HelloWorld.java b/java/01-helloworld/HelloWorld.java
new file mode 100644
index 0000000..299d161
--- /dev/null
+++ b/java/01-helloworld/HelloWorld.java
@@ -0,0 +1,5 @@
+public class HelloWorld {
+    public static void main(String[] args) {
+        System.out.println("Hello World!");
+    }
+}    
diff --git a/java/02-hello/.gitignore b/java/02-hello/.gitignore
new file mode 100644
index 0000000..6b468b6
--- /dev/null
+++ b/java/02-hello/.gitignore
@@ -0,0 +1 @@
+*.class
diff --git a/java/02-hello/Hello.java b/java/02-hello/Hello.java
new file mode 100644
index 0000000..bacee99
--- /dev/null
+++ b/java/02-hello/Hello.java
@@ -0,0 +1,5 @@
+public class Hello {
+    public static void main(String[] args) {
+        System.out.println("Hello " + args[0]);
+    }
+}
diff --git a/java/03-count/.gitignore b/java/03-count/.gitignore
new file mode 100644
index 0000000..6b468b6
--- /dev/null
+++ b/java/03-count/.gitignore
@@ -0,0 +1 @@
+*.class
diff --git a/java/03-count/Count.java b/java/03-count/Count.java
new file mode 100644
index 0000000..cbc651e
--- /dev/null
+++ b/java/03-count/Count.java
@@ -0,0 +1,29 @@
+public class Count {
+    public static void main(String[] args) {
+	if (args.length < 2) {
+	    System.err.println("[ERROR] Type two integers as arguments.");
+	    System.exit(1);
+	}
+
+	int start = 0;
+	int end = 0;
+	
+	try {
+	    start = Integer.parseInt(args[0]);
+	    end = Integer.parseInt(args[1]);
+	} catch(NumberFormatException nfe) {
+            System.err.println("[ERROR] You didn't provide integer arguments.");
+	    //System.err.println("Details: " + nfe.getMessage());
+	    System.exit(2);
+	}
+
+	if(start > end) {
+	    System.err.println("[ERROR] Start is greater than end.");
+	    System.exit(3);
+	}
+
+        for(int i = start; i <= end; i++) {
+            System.out.println(i);
+	}
+    }
+}
diff --git a/java/04-factorial/.gitignore b/java/04-factorial/.gitignore
new file mode 100644
index 0000000..6b468b6
--- /dev/null
+++ b/java/04-factorial/.gitignore
@@ -0,0 +1 @@
+*.class
diff --git a/java/04-factorial/Factorial.java b/java/04-factorial/Factorial.java
new file mode 100644
index 0000000..0b2e650
--- /dev/null
+++ b/java/04-factorial/Factorial.java
@@ -0,0 +1,21 @@
+public class Factorial {
+    public static void main(String[] args) {
+        int x = factorial(5);
+
+        System.out.println(x);
+
+        int y = factorial(10);
+
+        System.out.println(y);
+
+        System.out.println(factorial(3));
+    }
+
+    public static int factorial(int x) {
+        if (x == 0) {
+            return 1;
+        }
+
+        return x * factorial(x - 1);
+    }
+}