我很抱歉提前代码很长 - 但是他们阅读和理解非常简单，因为我是初学者。
问题在于我试图获得此输出：
Black Image Constructor:
(0,0,0) (0,0,0) (0,0,0) (0,0,0)
(0,0,0) (0,0,0) (0,0,0) (0,0,0)
(0,0,0) (0,0,0) (0,0,0) (0,0,0)
Constructor with RGBColor[][] Array Parameter:
(0,0,0) (0,0,0) (0,0,0) (0,0,0)
(1,1,1) (1,1,1) (1,1,1) (1,1,1)
(2,2,2) (2,2,2) (2,2,2) (2,2,2)
而不是那样，我只是犯了错误。
以下是我的3个代码：
RGBColor类：
/**
* This program is used to represent 3 Colors: Red, Green, Blue. (RGB)
* These colors hold values between 0 and 255.
*
*
* @Author Ilan Aizelman.
*/
public class RGBColor {
/**
* attributes: red, green and blue component of a color.
*/
private int _red,_green,_blue;
/**
* final variables.
*/
private final int MAX_VALUE = 255,MIN_VALUE = 0;
private final double THIRTY_PERCENT = 0.3,FIFTY_NINE_PERCENT = 0.59,ELEVEN_PERCENT = 0.11;
/**
* Consctructor which gets 3 colors (RGB), we check here if their range is valid (0 - 255), if not we assign black to it.
*
* @param red - The red color component value.
* @param green - The green color component value.
* @param blue - The blue color component value
*/
public RGBColor(int red, int green, int blue)
{
if(isValid(red,green,blue))
{
_red = red;
_green = green;
_blue = blue;
}
else
doBlack();
}
/**
* Construct a black RGBColor. i.e. red = green = blue = 0
*/
public RGBColor()
{
doBlack();
}
/**
* Here we check if the color number was entered correctly.
* It has to be an integer (whole number) between 0-255.
*
* @param nums - a component value, should be the number between 1-4
* @param return - return true if the number is between 1-4, false otherwise.
*/
private boolean isValid(int nums)
{
return ((nums >= MIN_VALUE) && (nums <= MAX_VALUE));
}
/**
* Here we check if the color number was entered correctly.
* It has to be an integer (whole number) between 0-255.
*
* @param red - the red component
* @param green - the green component
* @param blue - the red component
* @param return true if values are correct, false otherwise.
*/
private boolean isValid(int red, int green, int blue)
{
return ((red <= MAX_VALUE && red >= MIN_VALUE &&
green <= MAX_VALUE && green >= MIN_VALUE &&
blue <= MAX_VALUE && blue >= MIN_VALUE));
}
/**
* Returns RGB color string triplet with numbers between 0-255, i.e. (0,127,127)
*/
public String toString()
{
return ("(" + _red + "," + _green + "," + _blue + ")");
}
/**
* RGBColor will become the color Black. (0,0,0)
*/
private void doBlack()
{
_red = _green = _blue = 0;
}
}
RGBImage类：
public class RGBImage
{
private int _rows, _cols;
final int ZERO_VALUE = 0;
private RGBColor[][] _pixels;
/**
* Constructor for objects of class RGBImage
*/
public RGBImage(int rows, int cols)
{
_rows = rows;
_cols = cols;
_pixels = new RGBColor[_rows][_cols];
for(int i = 0; i < _rows; i++)
{
for(int j = 0; j < _cols; j++)
{
_pixels[i][j] = new RGBColor();
}
//System.out.println();
}
}
public RGBImage(RGBColor[][] pixels)
{
_pixels = new RGBColor[pixels.length][pixels[0].length];
for(int i = 0; i < pixels.length; i++)
{
for(int j 0; j < pixels[0].length; j++)
{
_pixels[i][j] = new RGBColor(pixels[i][j]);
}
}
}
}
和我的StudentTester类必须打印我在开头写的输出：
public class StudentTester {
public static void main(String[] args) {
System.out.println("Black Image Constructor:");
RGBImage rgbImg0 = new RGBImage(3,4);
System.out.println(rgbImg0);
System.out.println("Constructor with RGBColor[][] Array Parameter:");
RGBColor[][] rgbArray1 = new RGBColor[3][4];
for (int i=0; i<rgbArray1.length;i++)
for (int j=0; j<rgbArray1[0].length;j++)
rgbArray1[i][j] = new RGBColor(i,i,i);
RGBImage rgbImg1 = new RGBImage(rgbArray1);
System.out.println(rgbImg1);
System.out.println("Have a Nice Work!");
}
}
错误是：
Black Image Constructor:
RGBImage@47520d
Constructor with RGBColor[][] Array Parameter:
RGBImage@1aa4b35
Have a Nice Work!
编辑：
我现在已经添加了这个，
I've added this:
public String toString() {
String pixelSet="";
for(int i=0; i<_rows;i++){
for(int j=0 ;j<_cols;j++){
pixelSet+=this._pixels[i][j].toString();
}
pixelSet +="\n";
}
return pixelSet;
}
我没有得到＆＃34;构造函数与RGBColor [] []数组参数：＆＃34;输出了。还在努力，谢谢你们！
解决方案：（edit2）
public RGBImage(RGBColor[][] pixels)
{
_rows = pixels.length;
_cols = pixels[0].length;
_pixels = new RGBColor[_rows][_cols];
for(int i = 0; i < _rows; i++)
{
for(int j = 0; j < _cols; j++)
{
_pixels[i][j] = new RGBColor(pixels[i][j]);
}
}
}
答案 0 :(得分：2)
在这里打印一个物体。
System.out.println(rgbImg0);
但是你没有定义打印RGBImage对象时想要发生的事情。将对象引用传递给print语句时，将调用对象toString();方法并打印出结果。默认情况下，Object子类会打印出一个引用，例如RGBImage@47520d，即ClassName + @ + Hashcode。
您可以覆盖toString()的{{1}}方法来打印您需要的内容。
RGBColor然后，您可以覆盖@Override
public String toString() {
return "("+_red+","+_green+","+_blue+")";
}
类的toString()方法，以打印RGBImage个对象的数组。
RBGColor我希望这会有所帮助。
答案 1 :(得分：2)
你好@Illan Aizelman WS，
我没有在代码中看到任何编译错误，但是看看输出我可以看到你得到的是你要打印的对象的toString表示。如果您想获得问题中指明的输出，只需覆盖toString中java.lang.Object类的RGBImage方法即可。如果您直接尝试使用System.out.printXX打印对象，则无法获得所需的输出。请参阅以下步骤。
toString课程中的RGBImage方法。toString方法迭代数组。答案 2 :(得分：0)
您还必须在RgbImage类中实现toString（类似于您的RgbColor类）。标准实现只是打印RgbImage实例的objectId。
想想如果打印RgbImage实例会发生什么。例如，您可以调用该图像的所有单个像素的toString，您可以应用一些额外的格式等等。