Java - 找不到符号?
Java - Cannot find symbol?
我在这里练习了一点,但就是想不通。我声明了 ArrayList ns 但找不到它:
错误:找不到符号 ns.Add(aa);
为什么?当然,我根本看不到明显的东西。
import javax.swing.*;
import java.awt.*;
import java.awt.image.*;
import java.awt.event.*;
import java.util.Random;
import java.util.*;
import java.io.*;
public class Pixels6 extends JFrame
{
static java.util.List ns = new ArrayList();
class PaintingComponent extends JPanel
{
public void paintComponent(Graphics g)
{
super.paintComponent(g);
setBackground(Color.black);
}
}
public static void main( String[] args ) throws InterruptedException, IOException
{
try
{
fl = new FileInputStream("test_for_java2.s8");
aa = fl.read();
javax.swing.Timer swTimer = new javax.swing.Timer( 10, new ActionListener()
{
public void actionPerformed(ActionEvent ae)
{
if (aa!=-1)
{
aa -= 128;
aa = -aa;
ns.Add(aa);
try
{aa=fl.read(); }
catch( IOException e )
{
System.out.println( "Access denied: " + e );
System.out.println( e );
}
}
else try
{fl.close();}
catch( IOException e )
{
System.out.println( "Access denied: " + e );
System.out.println( e );
}
} /// Action
}); /// Timer
swTimer.start();
} //try
catch( IOException e )
{
System.out.println( "Access denied: " + e );
System.out.println( e );
}
SwingUtilities.invokeLater( new Runnable()
{
public void run()
{
new Pixels6().setVisible(true);
}
});
} /// main
} /// Pixels6 extends JFrame
改为
ns.add(aa); //not ns.Add(aa);
java 是区分大小写的语言
我在这里练习了一点,但就是想不通。我声明了 ArrayList ns 但找不到它: 错误:找不到符号 ns.Add(aa); 为什么?当然,我根本看不到明显的东西。
import javax.swing.*;
import java.awt.*;
import java.awt.image.*;
import java.awt.event.*;
import java.util.Random;
import java.util.*;
import java.io.*;
public class Pixels6 extends JFrame
{
static java.util.List ns = new ArrayList();
class PaintingComponent extends JPanel
{
public void paintComponent(Graphics g)
{
super.paintComponent(g);
setBackground(Color.black);
}
}
public static void main( String[] args ) throws InterruptedException, IOException
{
try
{
fl = new FileInputStream("test_for_java2.s8");
aa = fl.read();
javax.swing.Timer swTimer = new javax.swing.Timer( 10, new ActionListener()
{
public void actionPerformed(ActionEvent ae)
{
if (aa!=-1)
{
aa -= 128;
aa = -aa;
ns.Add(aa);
try
{aa=fl.read(); }
catch( IOException e )
{
System.out.println( "Access denied: " + e );
System.out.println( e );
}
}
else try
{fl.close();}
catch( IOException e )
{
System.out.println( "Access denied: " + e );
System.out.println( e );
}
} /// Action
}); /// Timer
swTimer.start();
} //try
catch( IOException e )
{
System.out.println( "Access denied: " + e );
System.out.println( e );
}
SwingUtilities.invokeLater( new Runnable()
{
public void run()
{
new Pixels6().setVisible(true);
}
});
} /// main
} /// Pixels6 extends JFrame
改为
ns.add(aa); //not ns.Add(aa);
java 是区分大小写的语言