用Java编写定义一个Teacher类，有姓名和学科2个属性，之后创建3个teacher对象并赋值，然后存入集合中，用曾强for遍历集合，控制台打印每个老师的信息

好的，下面是用Java编写的Teacher类的示例代码：

public class Teacher {
    private String name;
    private String subject;

    public Teacher(String name, String subject) {
        this.name = name;
        this.subject = subject;
    }

    public String getName() {
        return name;
    }

    public String getSubject() {
        return subject;
    }
}

接下来，我们可以创建三个Teacher对象，并将它们存入集合中，使用增强for循环遍历集合，并打印每个老师的信息。下面是示例代码：

import java.util.ArrayList;
import java.util.List;

public class Main {
    public static void main(String[] args) {
        List<Teacher> teachers = new ArrayList<>();

        Teacher teacher1 = new Teacher("Alice", "Math");
        Teacher teacher2 = new Teacher("Bob", "English");
        Teacher teacher3 = new Teacher("Charlie", "Science");

        teachers.add(teacher1);
        teachers.add(teacher2);
        teachers.add(teacher3);

        for (Teacher teacher : teachers) {
            System.out.println("Name: " + teacher.getName());
            System.out.println("Subject: " + teacher.getSubject());
            System.out.println();
        }
    }
}

运行上述代码，将会输出每个老师的姓名和学科信息。例如：

Name: Alice
Subject: Math

Name: Bob
Subject: English

Name: Charlie
Subject: Science

希望这个示例能够帮到你！如果还有其他问题，请随时提问。