public class Context {
}

abstract class AbstractExpression {
  public abstract void interpret(Context context);
}

public class TerminalExpression extends AbstractExpression {
  public void interpret(Context context) {
    System.out.println("TerminalExpression interpret(Context)メソッド");
  }
}

public class NonterminalExpression extends AbstractExpression {
  public void interpret(Context context) {
    System.out.println("NonterminalExpression interpret(Context)メソッド");
  }
}

import java.util.*;

public class Client {
  public static void main(String[] args) {
    Context c = new Context();

    ArrayList list = new ArrayList();

    list.add(new TerminalExpression());
    list.add(new NonterminalExpression());
    list.add(new TerminalExpression());
    list.add(new TerminalExpression());
    list.add(new TerminalExpression());

    for (int i=0;i<list.size();i++) {
      AbstractExpression exp = (AbstractExpression)list.get(i);
      exp.interpret(c);
    }
  }
}

C:\JavaHello\Interpreter>java Client
TerminalExpression interpret(Context)メソッド
NonterminalExpression interpret(Context)メソッド
TerminalExpression interpret(Context)メソッド
TerminalExpression interpret(Context)メソッド
TerminalExpression interpret(Context)メソッド

C:\JavaHello\Interpreter>