第 1 页 共 3 页
JAVA 语言题目
四、写出下面程序运行结果(每小题 6 分，共 30 分)
3、
class NoteX {
public static final int
MIDDLE_C = 0, C_SHARP = 1, C_FLAT = 2;
}
class InstrumentX {
public void play(int NoteX) {
System.out.println("InstrumentX.play()");
}
}
class WindX extends InstrumentX {
public void play(NoteX n) {
System.out.println("WindX.play(NoteX n)");
}
}
class KettleX extends InstrumentX {
public void play(int NoteX) {
System.out.println("KettleX.play(NoteX n)");
}
}
public class WindMusic {
public static void tune(InstrumentX i) {
i.play(NoteX.MIDDLE_C);
}
public static void main(String[] args) {
WindX flute = new WindX();
tune(flute);
KettleX kttle = new KettleX();
tune(kttle);
}
}
输出: InstrumentX.play()
KettleX.play(NoteX n)
4、
class Tags {
Tags(int marker) {
System.out.println("Tags(" + marker +
")");
}
}
class Insect {
Tags t1 = new Tags(1);
int i = 9;
int j;
Insect() {
prt("i = " + i + ", j = " + j);
j = 39;
}
static int x1 = prt("static Insect.x1
initialized");
Tags t2 = new Tags(2);
static int prt(String s) {
System.out.println(s);
return 47;
}
}
public class Beetle
extends Insect {
Tags t3 = new Tags(3);
int k = prt("Beetle.k initialized");
Beetle() {
prt("k = " + k);
prt("j = " + j);
}
static int x2 = prt("static Beetle.x2
initialized");
static int prt(String s) {
System.out.println(s);
return 63;
}
public static void main(String[] args) {
prt("Beetle constructor");
Beetle b = new Beetle();
}
}
