What is the difference between Builder Design pattern and Factory Design pattern? [closed]

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What is the difference between the Builder design pattern and the Factory design pattern?

Which one is more advantageous and why ?

How do I represent my findings as a graph if I want to test and compare/contrast these patterns ?

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A factory is simply a wrapper function around a constructor (possibly one in a different class). The key difference is that a factory method pattern requires the entire object to be built in a single method call, with all the parameters passed in on a single line. The final object will be returned.

A builder pattern, on the other hand, is in essence a wrapper object around all the possible parameters you might want to pass into a constructor invocation. This allows you to use setter methods to slowly build up your parameter list. One additional method on a builder class is a build() method, which simply passes the builder object into the desired constructor, and returns the result.

In static languages like Java, this becomes more important when you have more than a handful of (potentially optional) parameters, as it avoids the requirement to have telescopic constructors for all the possible combinations of parameters. Also a builder allows you to use setter methods to define read-only or private fields that cannot be directly modified after the constructor has been called.

Basic Factory Example

// Factory
static class FruitFactory {
    static Fruit create(name, color, firmness) {
        // Additional logic
        return new Fruit(name, color, firmness);
    }
}

// Usage
Fruit fruit = FruitFactory.create("apple", "red", "crunchy");

Basic Builder Example

// Builder
class FruitBuilder {
    String name, color, firmness;
    FruitBuilder setName(name)         { this.name     = name;     return this; }
    FruitBuilder setColor(color)       { this.color    = color;    return this; }
    FruitBuilder setFirmness(firmness) { this.firmness = firmness; return this; }
    Fruit build() {
        return new Fruit(this); // Pass in the builder
    }
}

// Usage
Fruit fruit = new FruitBuilder()
        .setName("apple")
        .setColor("red")
        .setFirmness("crunchy")
        .build();

It may be worth comparing the code samples from these two wikipedia pages:

http://en.wikipedia.org/wiki/Factory_method_pattern
http://en.wikipedia.org/wiki/Builder_pattern

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