객체/모델의 단방향 연관 및 양방향 연관

일대일

1. 단방향(X->Y)

package com.xs;

public class X {
	private Y y;

	public Y getY() {
		return y;
	}

	public void setY(Y y) {
		this.y = y;
	}
	
	
}

package com.xs;

public class Y {

}

2. 양방향

package com.xs;

public class X {
	private Y y;

	public Y getY() {
		return y;
	}

	public void setY(Y y) {
		this.y = y;
	}
}

package com.xs;

public class Y {
	private X x;

	public X getX() {
		return x;
	}

	public void setX(X x) {
		this.x = x;
	}

}

다대일

1. 단방향(X->Y)

package com.xs;

public class X {
	private Y y;

	public Y getY() {
		return y;
	}

	public void setY(Y y) {
		this.y = y;
	}
}

package com.xs;

public class Y {

}

2. 양방향

package com.xs;

public class X {
	private Y y;

	public Y getY() {
		return y;
	}

	public void setY(Y y) {
		this.y = y;
	}
}

package com.xs;

import java.util.HashSet;
import java.util.Set;

public class Y {
	private Set<X> xs = new HashSet<X>();

	public Set<X> getXs() {
		return xs;
	}

	public void setXs(Set<X> xs) {
		this.xs = xs;
	}
}

셋:한 쌍

1. 단방향(X->Y)

package com.xs;

import java.util.HashSet;
import java.util.Set;

public class X {
	private Set<Y> ys = new HashSet<Y>();

	public Set<Y> getYs() {
		return ys;
	}

	public void setYs(Set<Y> ys) {
		this.ys = ys;
	}
}

package com.xs;

public class Y {

}

2. 양방향

package com.xs;

import java.util.HashSet;
import java.util.Set;

public class X {
	private Set<Y> ys = new HashSet<Y>();

	public Set<Y> getYs() {
		return ys;
	}

	public void setYs(Set<Y> ys) {
		this.ys = ys;
	}
}

package com.xs;

public class Y {
	private X x;

	public X getX() {
		return x;
	}

	public void setX(X x) {
		this.x = x;
	}
}

다대다

1. 단방향(X->Y)

package com.xs;

import java.util.HashSet;
import java.util.Set;

public class X {
	private Set<Y> ys = new HashSet<Y>();

	public Set<Y> getYs() {
		return ys;
	}

	public void setYs(Set<Y> ys) {
		this.ys = ys;
	}
}

package com.xs;

public class Y {
}

2. 양방향

package com.xs;

import java.util.HashSet;
import java.util.Set;

public class X {
	private Set<Y> ys = new HashSet<Y>();

	public Set<Y> getYs() {
		return ys;
	}

	public void setYs(Set<Y> ys) {
		this.ys = ys;
	}
}

package com.xs;

import java.util.HashSet;
import java.util.Set;

public class Y {
	private Set<X> xs = new HashSet<X>();

	public Set<X> getXs() {
		return xs;
	}

	public void setXs(Set<X> xs) {
		this.xs = xs;
	}
}