标签：cmd
作者：郭嘉
邮箱：allenwells@163.com
博客：http://blog.csdn.net/allenwells
github：https://github.com/AllenWell
原理：
Process process = Runtime.getRuntime().exec("cmd order");注意：
如果exec()中只有CMD命令，则命令会直接被执行，而不会打开命令行窗口；
举例：
下面例子实现了执行解压JAR包，并把命令行信息输到Java的图形界面的功能：
Process process = null;
try
{
process = Runtime.getRuntime().exec("jar xvf " + jarInputFile.getPath()) ;
}
catch (IOException e)
{
e.printStackTrace();
}
InputStream inputStream = process.getInputStream();
Reader reader = new InputStreamReader(inputStream);
BufferedReader bufferedReader = new BufferedReader(reader);
try
{
for(String s = ""; ( s = bufferedReader.readLine()) != null;)
{
consoleInfo.append(s + "<br>");
}
bufferedReader.close();
reader.close();
JLabel consoleLabel = new JLabel();
consoleLabel.setText("<html>" + consoleInfo.toString() + "</html>");
}
}
catch (/ e)
{
e.printStackTrace();
}注意：Java Swing的文字显示不支持直接“\n”换行，所以使用“”标签的形式来实现换行。
以上程序展示的是把执行一条命令后，把命令行上的信息输出到Java的图形界面上，那么如何实现实时的检测Windows的命令行打印信息并进行输出呢？
实现方法：
Java的System类中有个out成员变量，称为标准输出流，用来把打印输出到屏幕上。上面所述的问题其实就是System.out的输出重定向问题。
System.out在Java中源码实现如下所示：
/**
* Default input stream.
*/
public static final InputStream in;
/**
* Default output stream.
*/
public static final PrintStream out;
/**
* Default error output stream.
*/
public static final PrintStream err;
private static final String lineSeparator;
private static Properties systemProperties;
static {
err = new PrintStream(new FileOutputStream(FileDescriptor.err));
out = new PrintStream(new FileOutputStream(FileDescriptor.out));
in = new BufferedInputStream(new FileInputStream(FileDescriptor.in));
lineSeparator = System.getProperty("line.separator");
}从上面可以看出，System.out是一个PrintStream。只需要把它重定向到我们需要的地方就可以了，具体代码实现如下所示：
package com.allenwells.ui;
import java.awt.Color;
import java.awt.Dimension;
import java.io.OutputStream;
import java.io.PrintStream;
import javax.swing.JScrollPane;
import javax.swing.JTextPane;
import javax.swing.SwingUtilities;
import javax.swing.text.AbstractDocument;
import javax.swing.text.BadLocationException;
import javax.swing.text.Document;
import javax.swing.text.Element;
import javax.swing.text.Style;
import javax.swing.text.StyleConstants;
import javax.swing.text.StyledDocument;
public class ConsolePane extends JScrollPane
{
private static final long serialVersionUID = 1L;
private JTextPane textPane = new JTextPane();
private static ConsolePane console = null;
public static synchronized ConsolePane getInstance()
{
if (console == null)
{
console = new ConsolePane();
}
return console;
}
private ConsolePane()
{
setViewportView(textPane);
// Set up System.out
PrintStream mySystemOut = new MyPrintStream(System.out, Color.black);
System.setOut(mySystemOut);
// Set up System.err
PrintStream mySystemErr = new MyPrintStream(System.err, Color.red);
System.setErr(mySystemErr);
textPane.setEditable(true);
setPreferredSize(new Dimension(640, 120));
}
/**
* Returns the number of lines in the document.
*/
private final int getLineCount()
{
return textPane.getDocument().getDefaultRootElement().getElementCount();
}
/**
* Returns the start offset of the specified line.
*
* @param line
* The line
* @return The start offset of the specified line, or -1 if the line is
* invalid
*/
private int getLineStartOffset(int line)
{
Element lineElement = textPane.getDocument().getDefaultRootElement()
.getElement(line);
if (lineElement == null)
return -1;
else
return lineElement.getStartOffset();
}
/**
* 清除超过行数时前面多出行的字符
*/
private void replaceRange(String str, int start, int end)
{
if (end < start)
{
throw new IllegalArgumentException("end before start");
}
Document doc = textPane.getDocument();
if (doc != null)
{
try
{
if (doc instanceof AbstractDocument)
{
((AbstractDocument) doc).replace(start, end - start, str,
null);
}
else
{
doc.remove(start, end - start);
doc.insertString(start, str, null);
}
}
catch (BadLocationException e)
{
throw new IllegalArgumentException(e.getMessage());
}
}
}
class MyPrintStream extends PrintStream
{
private Color foreground; // 输出时所用字体颜色
/**
* 构造自己的 PrintStream
*
* @param out
* 可传入 System.out 或 System.err, 实际不起作用
* @param foreground
* 显示字体颜色
*/
MyPrintStream(OutputStream out, Color foreground)
{
super(out, true); // 使用自动刷新
this.foreground = foreground;
}
/**
* 在这里重截,所有的打印方法都要调用最底一层的方法
*/
public void write(byte[] buf, int off, int len)
{
final String message = new String(buf, off, len);
/** SWING非界面线程访问组件的方式 */
SwingUtilities.invokeLater(new Runnable()
{
public void run()
{
try
{
StyledDocument doc = (StyledDocument) textPane
.getDocument();
// Create a style object and then set the style
// attributes
Style style = doc.addStyle("StyleName", null);
// Foreground color
StyleConstants.setForeground(style, foreground);
doc.insertString(doc.getLength(), message, style);
}
catch (BadLocationException e)
{
// e.printStackTrace();
}
// Make sure the last line is always visible
textPane.setCaretPosition(textPane.getDocument()
.getLength());
// Keep the text area down to a certain line count
int idealLine = 150;
int maxExcess = 50;
int excess = getLineCount() - idealLine;
if (excess >= maxExcess)
{
replaceRange("", 0, getLineStartOffset(excess));
}
}
});
}
}
}使用方法
JPanel contentPanel = new JPanel();
ConsolePane consolePane = ConsolePane.getInstance();
contentPanel.add(consolePane);效果图如下所示：
这里给出常见的CMD命令：
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标签：cmd
原文地址：http://blog.csdn.net/allenwells/article/details/46742227
