How can methods be defined in Java?

In Java, you can define a method using the following syntax:

Access modifier Return type Method name(Parameter list) {
// Method body
}

Access modifier: Specifies who can access the method, such as public, private, protected, etc. If no modifier is specified, it defaults to package-private.
Return type: The type of value that the method will return, can be any valid data type. If the method does not return any value, the void keyword can be used.
Method name: The name of the method, used to call the method from elsewhere.
Parameter list: The input parameters that the method accepts, can be zero or more parameters. Each parameter consists of a data type and parameter name.
Method body: The specific implementation of the method, which includes the code to be executed.

Here is an example:

Create a method called addNumbers that takes in two integer parameters, adds them together, and then returns the sum.

In the example above, we defined a method called addNumbers that takes two integers as parameters and returns the sum. Inside the method, we add the two input parameters together and store the result in a variable, then use the return keyword to send back the result.