问题描述
描述:实际上我正在查看基本上在后台运行的java代码,但是每当我想打开一个新的记事本或excel文件时,它都会捕获这些文件作为输入并在输出控制台中显示结果。
我该怎么做,任何人都可以帮助我。
解决方法
以下方法基于 Windows...
首先,在记事本、Excel等软件中打开文件时,是用带参数的命令行执行的,即如果记事本在E:\test.txt中打开,启动的命令行参数为
notepad E:\test.txt
在 Windows 中,我们可以使用 wmic 命令来获取应用程序的启动参数。具体用法是:
wmic process where caption="{exe_name}" get caption,commandline /value
例如查询记事本中打开的命令行参数的cmd命令是:
wmic process where caption="notepad.exe" get caption,commandline /value
返回结果类似如下:
Caption=notepad.exe
CommandLine="C:\Windows\system32\NOTEPAD.EXE" H:\2019Summer\软件工程\任务.txt
上面的“H:\2019Summer\软件工程\任务.txt”是我目前用记事本打开的文件。 我们需要做的是解析结果String,这里是我的示例java代码:
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.text.MessageFormat;
import java.util.ArrayList;
import java.util.List;
import java.util.stream.Collectors;
public class GetOpenedFile {
//QUERY_COMMAND
private static String QUERY_COMMAND = "wmic process where caption=\"{0}\" get caption,commandline /value";
private static String NOTEPAD_NAME = "notepad.exe";
private static String EXCEL_NAME = "excel.exe";
/**
* get execName command line
*
* @param execName like notepad.exe,excel.exe
* @return the all command line of the process {execName}
*/
private static List<String> getExecCommandLines(String execName) {
Runtime runtime = Runtime.getRuntime();
List<String> commandLines = new ArrayList<>();
try {
Process process = runtime.exec(MessageFormat.format(QUERY_COMMAND,execName));
BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(process.getInputStream(),"GB2312"));//set your cmd charset(default value is utf8)
String caption = null;
while (true) {
String s = bufferedReader.readLine();
if (s == null) {
break;
}
if (s.length() == 0) {//skip blank string
continue;
}
//get the file name
if (s.startsWith("Caption")) {
caption = s.substring("Caption=".length());
continue;
}
if (s.startsWith("CommandLine=") && caption != null) {
int index = Math.max(s.indexOf(caption),s.indexOf(caption.toUpperCase()));//maybe the exe file name is ALL UPPER CASE,eg. NOTEPAD.EXE
index += caption.length()
+ 1;//Double quotes "
String commandLine = s.substring(index);// command Line
commandLine = commandLine.stripLeading();//strip leading white space
commandLines.add(commandLine);
}
}
} catch (IOException e) {
e.printStackTrace();
}
return commandLines;
}
/**
* get notepad opened files
*
* @return notepad opened files
*/
public static List<String> getNotepadOpenedFiles() {
List<String> commandLines = getExecCommandLines(NOTEPAD_NAME);
return commandLines.stream()
.filter(s -> s.length() > 0)//skip empty command line
.collect(Collectors.toList());
}
/**
* get excel opened files
* @return excel opened files
*/
public static List<String> getExcelOpenedFiles() {
List<String> commandLines = getExecCommandLines(EXCEL_NAME);
return commandLines.stream()
.filter(s -> s.length() > 0)//skip empty command line
.map(s -> { //map result of "filename" to filename
if (s.startsWith("\"") && s.endsWith("\"")) {
return s.substring(1,s.length() - 1);
} else {
return s;
}
})
.collect(Collectors.toList());
}
public static void main(String[] args) {
//console printed
// [H:\2019Summer\软件工程\任务.txt]
// [E:\info.xlsx]
System.out.println(getNotepadOpenedFiles());
System.out.println(getExcelOpenedFiles());
}
}