can you have two conditions in an if statement

Question

I'm a beginner in coding. I was recently working with to create a chatting programme where a user will chat with my computer. Here is a part of the code:

System.out.println("Hello, what's our name? My name is " + answer4);
String a = scanner1.nextLine();
System.out.println("Ok, Hello, " + a + ", how was your day, good or bad?");
String b = scanner2.nextLine();

**if (b.equals("good"))** {                //1
    System.out.println("Thank goodness");
} else **if (b.equals("it was good"))** {  //2
    System.out.println("Thank goodness");
} else **if (b.equals("bad"))** {          //3
    System.out.println("Why was it bad?");
    String c = scanner3.nextLine();
    System.out.println("Don't worry, everything will be ok, ok?");
    String d= scanner10.nextLine();
} else **if (b.equals("it was bad"))**{    //4
    System.out.println("Why was it bad?");
    String c = scanner3.nextLine();
    System.out.println("Don't worry, everything will be ok, ok?");
    String d= scanner10.nextLine();
}

if(age<18){System.out.println("How was school?");}
else if (age>=18){System.out.println("How was work?");}

The conditions of the if statements are in Bold (surrounded with **). In case of first and the second condition I want my application to do same thing. Similarly third and fourth condition. I thought it was possible to somehow group them in if statement.

I tried with below code but it doesn't compile:

if (b.equals("good"), b.equals("it was good")) {
    System.out.println("Thank goodness");
}  else if (b.equals("bad"),(b.equals("it was bad"))) {
    System.out.println("Why was it bad?");
    String c = scanner3.nextLine();
    System.out.println("Don't worry, everything will be ok, ok?");
    String d= scanner10.nextLine();
}

Can someone correct it for me?

Answer 1

You can use logical operators to combine your boolean expressions.

• && is a logical and (both conditions need to be true)
• || is a logical or (at least one condition needs to be true)
• ^ is a xor (exactly one condition needs to be true)
• (== compares objects by identity)

For example:

if (firstCondition && (secondCondition || thirdCondition)) {
    ...
}

There are also bitwise operators:

• & is a bitwise and
• | is a bitwise or
• ^ is a xor

They are mainly used when operating with bits and bytes. However there is another difference, let's take again a look at this expression:

firstCondition && (secondCondition || thirdCondition)

If you use the logical operators and firstCondition evaluates to false then Java will not compute the second or third condition as the result of the whole logical expression is already known to be false. However if you use the bitwise operators then Java will not stop and continue computing everything:

firstCondition & (secondCondition | thirdCondition)

Answer 2

Here are some common symbols used in everyday language and their programming analogues:

• "," usually refers to "and" in everyday language. Thus, this would translate to the AND operator, &&, in Java.
• "/" usually refers to "or" in everyday language. Thus, this would translate to the OR operator, ||, in Java.

"XOR" is simply "x || y but both cannot be true at the same time". This translates to x ^ y in Java.

In your code, you probably meant to use "or" (you just used the incorrect "incorrect solution" :p), so you should use "||" in the second code block for it to become identical to the first code block.

Hope this helped :)