gistfile1.java

public interface ICondition<T> {
	boolean isSatisfiedBy(T object);
	ICondition<T> negate();
	ICondition<T> and(ICondition<T> other);
	ICondition<T> or(ICondition<T> other);
}

package com.maptimize.conditions;

public abstract class AbstractCondition<T> implements ICondition<T> {
	public ICondition<T> negate() {
//		final ICondition<T> self = this;
		return new AbstractCondition<T>() {
			public boolean isSatisfiedBy(T object) {
				// Does the same thing, surprisingly
				return !AbstractCondition.this.isSatisfiedBy(object);
			}
		};
	}
	
	public ICondition<T> and(final ICondition<T> other) {
//		final ICondition<T> self = this;
		return new AbstractCondition<T>() {
			public boolean isSatisfiedBy(T object) {
				return AbstractCondition.this.isSatisfiedBy(object) && other.isSatisfiedBy(object);
			}
		};
	}
	
	public ICondition<T> or(final ICondition<T> other) {
//		final ICondition<T> self = this;
		return new AbstractCondition<T>() {
			public boolean isSatisfiedBy(T object) {
				return AbstractCondition.this.isSatisfiedBy(object) || other.isSatisfiedBy(object);
			}
		};
	}
}