配列の勉強する

１次元配列の定義、値変更、配列全体の参照渡し

sample.java

public class Mavenproject1 {
    int i1[];
    int i2[];
    public Mavenproject1() {
        i1 = new int[2];
        i2 = new int[2];        
    }
    public static void main(String[] args) {
        Mavenproject1 m = new Mavenproject1();
        m.i1[0] = 1;
        m.i1[1] = 1;
        m.i2[0] = 2;
        m.i2[1] = 2;
        m.putlog();
        m.i2 = m.i1;
        m.i1[1] = 3;
        m.putlog();
    }
    public void putlog(){
        System.out.println("i1[0] = " + i1[0]);
        System.out.println("i1[1] = " + i1[1]);
        System.out.println("i2[0] = " + i2[0]);
        System.out.println("i2[1] = " + i2[1]);
        System.out.println("------------------");
    }
}

i1[0] = 1
i1[1] = 1
i2[0] = 2
i2[1] = 2
------------------
i1[0] = 1
i1[1] = 3
i2[0] = 1
i2[1] = 3
------------------

配列初期化子

sample.java

    public static void main(String[] args) {
        int i1[] = {1,2,3};
        System.out.println("i1[0] = " + i1[0]);
        System.out.println("i1[1] = " + i1[1]);
        System.out.println("i1[2] = " + i1[2]);
    }

i1[0] = 1
i1[1] = 2
i1[2] = 3

２次元配列の定義

sample.java

    public static void main(String[] args) {
        int i1[][] = new int[2][2];
        i1[0][0] = 1;
        i1[0][1] = 2;
        i1[1][0] = 3;
        i1[1][1] = 4;
    }