① 怎么编写java程序实现图片的移动(最好有例子)
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Image;
import java.awt.event.KeyAdapter;
import java.awt.event.KeyEvent;
import javax.swing.JFrame;
public class DrawTest extends JFrame {
private int x = 50;
private int y = 50;
private Image offScreenImage = null;
@Override
public void paint(Graphics g) {
Color c = g.getColor();
g.setColor(Color.BLACK);
g.fillOval(x, y, 30, 30);
g.setColor(c);
}
public void update(Graphics g) {
if (offScreenImage == null) {
offScreenImage = this.createImage(500, 500);
}
Graphics gOffScreen = offScreenImage.getGraphics();
Color c = gOffScreen.getColor();
gOffScreen.setColor(Color.GREEN);
gOffScreen.fillRect(0, 0, 500, 500);
gOffScreen.setColor(c);
paint(gOffScreen);
g.drawImage(offScreenImage, 0, 0, null);
}
public static void main(String[] args) {
DrawTest d = new DrawTest();
}
public DrawTest() {
init();
addKeyListener(new KeyAdapter() {
public void keyPressed(final KeyEvent e) {
int code = e.getKeyCode();
switch (code) {
case KeyEvent.VK_UP:
y -= 5;
break;
case KeyEvent.VK_RIGHT:
x += 5;
break;
case KeyEvent.VK_DOWN:
y += 5;
break;
case KeyEvent.VK_LEFT:
x -= 5;
break;
}
}
});
}
public void init() {
this.setDefaultCloseOperation(this.EXIT_ON_CLOSE);
this.setBackground(Color.GREEN);
this.setResizable(false);
this.setBounds(140, 140, 500, 500);
this.setVisible(true);
MyThread mt = new MyThread();
new Thread(mt).start();
}
class MyThread implements Runnable {
public void run() {
while (true) {
repaint();
try {
Thread.sleep(100);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}
}
以上
② java读取pdf判断文字旋转方向
嗯……关于java读取pdf的话，推荐阁下试试pdfbox这个工具，能够支持中文，但是缺点在于不能读取图片形式的pdf，比如将一篇文章照下来，存成图片，做的pdf识别不了。如果阁下想要做图像方面的文字识别的话，可以考虑使用tesseract这个工具，同样识别中文！关于文字的旋转方向……在下的思路是每次将文字进行九十度旋转，并进行识别，能识别出来的时候，计算出旋转角度即可！思路仅供参考，祝阁下学习愉快！