我使用二维数组来表示使用（X，Y）坐标的网格。网格是80列乘30行。我正在使用重定向（java project1＆lt; project1.input）来为我的程序提供命令行。
这是project1.input的样子：
c
l 10 10 20 10 *
l 20 10 20 20 *
l 20 20 10 20 *
l 10 20 10 10 *
p 15 15 X
d
q
c =清除（重新初始化）
l =使用char（*）
从X1 Y1到X2 Y2画一条线p =使用char（X）
绘制X1 Y1处的点d =打印当前网格
q =退出
这是我的整个.java，由于某种原因它只能绘制单个点而不是打印线。我试过看看我的for循环设置点，我的getInput方法，但我找不到问题。
import java.util.Scanner;
import java.lang.*;
public class project1
{
// declaring class array named grid
public static char[][] grid = new char[80][30];
// method: main
// purpose: calls getInput and initGrid
public static void main(String[] args)
{
initGrid();
getInput();
}
// method: initGrid
// purpose: initializes the grid with spaces, also acts as the clear command
public static void initGrid()
{
char fill = '1';
for(int i = 0; i < grid.length; i++){
for(int j = 0; j < grid[0].length; j++){
grid[i][j] = fill;
}
}
}
// method: getInput
// purpose: gets the input and sends it to the appropriate method
public static void getInput()
{
char firstCharacter, drawCharacter;
int X1, Y1, X2, Y2;
Scanner in = new Scanner(System.in);
while(in.hasNextLine()){
firstCharacter = in.next().charAt(0);
if(firstCharacter == 'p'){
X1 = in.nextInt();
Y1 = in.nextInt();
drawCharacter = in.next().charAt(0);
in.nextLine();
plotPoint(X1, Y1, drawCharacter);
}
if(firstCharacter == 'l'){
X1 = in.nextInt();
Y1 = in.nextInt();
X2 = in.nextInt();
Y2 = in.nextInt();
drawCharacter = in.next().charAt(0);
in.nextLine();
drawLine(X1, Y1, X2, Y2, drawCharacter);
}
if(firstCharacter == 'c'){
in.nextLine();
initGrid();
}
if(firstCharacter == 'd'){
in.nextLine();
printGrid();
}
if(firstCharacter == 'q'){
return;
}
}
}
// method: plotPoint
// purpose: receives the p command and plots the point with given coordinates and char
public static void plotPoint(int X, int Y, char character)
{
grid[X][Y] = character;
}
// method: drawLine
// purpose: receives the l command and draws a line with given coordinates and char
public static void drawLine(int X1, int Y1, int X2, int Y2, char character)
{
int stopX = X1;
int stopY = Y1;
int stopX2 = X2;
int stopY2 = Y2;
// checks for horizontal line, left to right
if(Y1==Y2 && X1<X2){
for(int i = 0; stopX == stopX2; i++){
grid[X1+i][Y1] = character;
}
}
// checking for horizontal line, right to left
if(Y1==Y2 && X1>X2){
for(int i = 0; stopX2 == stopX; i--){
grid[X1+i][Y1] = character;
}
}
// checking for vertical line, top to bottom
if(X1==X2 && Y1<Y2){
for(int i = 0; stopY == stopY2; i++){
grid[X1][Y1+i] = character;
}
}
// checking for vertical line, bottom to top
if(X1==X2 && Y1>Y2){
for(int i = 0; stopY2 == stopY; i--){
grid[X1][Y1+i] = character;
}
}
}
// method: printGrid
// purpose: prints the grid to show the picture
public static void printGrid()
{
for(int j = 0; j < grid[0].length; j++){
for(int i = 0; i < grid.length; i++){
System.out.print(grid[i][j]);
if(i == grid.length-1){
System.out.println();
}
}
}
}
}
对于括号感到抱歉，它不会很好地复制出emacs。
答案 0 :(得分：3)
你的for循环不起作用，因为条件错误！
import java.util.Scanner;
import java.lang.*;
public class Grid
{
// declaring class array named grid
public static char[][] grid = new char[80][30];
// method: main
// purpose: calls getInput and initGrid
public static void main(String[] args)
{
initGrid();
getInput();
}
// method: initGrid
// purpose: initializes the grid with spaces, also acts as the clear command
public static void initGrid()
{
char fill = '1';
for(int i = 0; i < grid.length; i++){
for(int j = 0; j < grid[0].length; j++){
grid[i][j] = fill;
}
}
}
// method: getInput
// purpose: gets the input and sends it to the appropriate method
public static void getInput()
{
char firstCharacter, drawCharacter;
int X1, Y1, X2, Y2;
Scanner in = new Scanner(System.in);
while(in.hasNextLine()){
firstCharacter = in.next().charAt(0);
if(firstCharacter == 'p'){
X1 = in.nextInt();
Y1 = in.nextInt();
drawCharacter = in.next().charAt(0);
in.nextLine();
plotPoint(X1, Y1, drawCharacter);
}
if(firstCharacter == 'l'){
X1 = in.nextInt();
Y1 = in.nextInt();
X2 = in.nextInt();
Y2 = in.nextInt();
drawCharacter = '*';
in.nextLine();
drawLine(X1, Y1, X2, Y2, drawCharacter);
}
if(firstCharacter == 'c'){
in.nextLine();
initGrid();
}
if(firstCharacter == 'd'){
in.nextLine();
printGrid();
}
if(firstCharacter == 'q'){
return;
}
}
}
// method: plotPoint
// purpose: receives the p command and plots the point with given coordinates and char
public static void plotPoint(int X, int Y, char character)
{
grid[X][Y] = character;
}
// method: drawLine
// purpose: receives the l command and draws a line with given coordinates and char
public static void drawLine(int X1, int Y1, int X2, int Y2, char character)
{
// checks for horizontal line, left to right
if(Y1==Y2 && X1<X2){
for(int i = 0; i<= Math.abs(X2-X1); i++){
grid[X1+i][Y1] = character;
}
}
// checking for horizontal line, right to left
if(Y1==Y2 && X1>X2){
for(int i=02; i<=Math.abs(X2-X1); i++){
grid[X2+i][Y1] = character;
}
}
// checking for vertical line, top to bottom
if(X1==X2 && Y1<Y2){
for(int i = 0; i<=Math.abs(Y1-Y2); i++){
grid[X1][Y1+i] = character;
}
}
// checking for vertical line, bottom to top
if(X1==X2 && Y1>Y2){
for(int i = 0; i<=Math.abs(Y1-Y2); i++){
grid[X1][Y2+i] = character;
}
}
}
// method: printGrid
// purpose: prints the grid to show the picture
public static void printGrid()
{
for(int j = 0; j < grid[0].length; j++){
for(int i = 0; i < grid.length; i++){
System.out.print(grid[i][j]);
if(i == grid.length-1){
System.out.println();
}
}
}
}
}
试试这个！