Thread: Please Help me Find the Error

In the Following Simple programs im getting a common error. missing return statement. Please help me find the repeated error committed by me.

program 1:

import java.io.*;

class jugal
{
int i,j;
/* jugal(int i,int j)
{
this.i=i;
this.j=j;
}*/

public int disp(int i,int j)
{
this.i=i;
this.j=j;
return i+j;
}
}

class sample
{
public static Void main(String a1[])
{
jugal j1=new jugal();
System.out.println(j1.disp(5,5));
int a=Integer.parseInt(a1[0]);
int b=Integer.parseInt(a1[1]);
jugal j2=new jugal();
int c=j2.disp(a,b);
System.out.println("show" +c);
}
}


program 2:

interface example
{
final int a=5;
Void show();
}

class jugal implements example
{
public Void show()
{
System.out.println(a*a);
}

}

class sample1
{
public static Void main(String a1[])
{
jugal j1=new jugal();
j1.show();
}
}


program 3:

class jugal implements Runnable
{
Thread t;
jugal()
{
t=new Thread(this,"demo");
System.out.println(t);
t.start();
}
public Void run()
{
try
{
for(int i=1;i<10;i--);
{
System.out.println(i);
Thread.sleep(500);
}
}
catch(InterruptedException e)
{
System.out.println(e);
}
}
}

class sample2
{
public static Void main(String a[])
{
new jugal();
try
{
for(int i=1;i<10;i--);
{
System.out.println(i);
Thread.sleep(1000);
}
}
catch(InterruptedException e)
{
System.out.println(e);
}
}
}


program 4:


import java.util.*;

public class sample5
{
public static Void main(String a[])
{
int c[]={5,7,1,3,2};
Set<Integer> s=new HashSet<Integer>();

for(int i=0;i<5;i++)
{
s.add(c[i]);
}
System.out.println(s);

TreeSet ss=new TreeSet<Integer>(s);
System.out.println(ss.first());
System.out.println(ss.last());

}
}


program 5:

import java.util.*;

public class sample6
{
public static Void main(String a[])
{
int c[]={4,6,2,1,9};
List<Integer> l=new ArrayList<Integer>();

for(int i=0;i<5;i++)
{
l.add(c[i]);
}
System.out.println(c);

LinkedList<Integer> l1=new LinkedList<Integer>(l);

for(int i=0;i<5;i++)
{
l1.addFirst(c[i]);
}
System.out.println(l1.removeLast());
}
}


program 6:


import java.util.*;

public class sample7
{
public static Void main(String a[])
{
String s[]={"sun","mon","tues","wed","thrus"};

Map m=new HashMap();
for(int i=0;i<5;i++)
{
m.put(i,s[i]);
}
TreeMap t=new TreeMap(m);
System.out.println(t.keySet());
System.out.println(t.firstkey()+" value: "+t.get(t.firstKey()));
System.out.println(t.lastKey()+" "+t.get(t.lastKey()));
System.out.println(t.remove(t.lastkey()));
System.out.println(t.values());
System.out.println(t.keySet());
}
}


program 7:

import java.util.Vector;
import java.util.Enumeration;

class sample8
{
public static Void main(String a[])
{
Vector<Object> v=new Vector<Object>();
int p=20;
Integer i=new Integer(20);
String s=new String("Jugal");
v.add(i);
v.add(p);
v.add(s);
System.out.println(v);
v.add(2,new Integer(10));
System.out.println(v);
System.out.println(v.elementAt(2));
System.out.println(v.firstElement());
System.out.println(v.lastElement());
v.removeElementAt(2);
System.out.println(v);
System.out.println(v.firstElement());
System.out.println(v.lastElement());
Enumeration e=v.elements();
while(e.hasMoreElements())
{
System.out.println(e.nextElement());
}
}
}

Case matters in Java, so void is what we use if we don't return anything. And Void is something else which you almost certainly don't want to use (but if it is used then an instance of Void must be returned.)

can you help me understand the error, with an simple example.

Try to enclose your codes with [highlight = java] code here [/java] for easy reading by potential helpers.

can you help me understand the error, with an simple example.

Example:

public int returnSomething(int a,int b){
         return (a+b);
}

thanks for the rep. Im a beginner in java. Would plz make it more precise, like where im i suppose to use /java exactly.

Read the second reply to this thread and you will find the answer.

Look at the (V) in the main method. Try changing it to lowercase (v). Again, read the second response to your question.