java - 使用 java 属性文件时出现 FileNotFoundException

Question

我在做了很多研究之后问了这个问题，并在研究之后在我的代码中实现了它，但我最终得到了 FileNotFoundException。我在这里做的是我想避免在我的 java 代码中进行硬编码，所以我创建了一个属性名为 Constants.properties 的文件，并在我的 Java 代码中调用它。但它说它没有找到该文件。我的属性文件在项目的 src 文件夹中。下面是代码片段。有什么建议吗？

属性文件:

executable.run = C:\\server\\lrd.exe
incoming.file = C:\\file\\test.ic
executable.params1 = -z
executable.params2 = -a[+]
log.file = C:\\TESTFile\\test.txt

Java 代码:这是包含属性文件详细信息的类文件。

public class PropInfo {
    static private PropInfo _instance =  null;
    public String executable =  null;
    public String filein = null;
    public String params1 = null; 
    public String params2 = null; 
    public String log = null; 

    protected PropInfo(){
        try{
            InputStream file = new FileInputStream(new File("Constants.properties"));
            Properties props = new Properties();
            props.load(file);
            executable = props.getProperty("executable.run");
            filein = props.getProperty("incomin.file");
            params1 = props.getProperty("executable.params1");
            params2 = props.getProperty("executable.params2");
            log = props.getProperty("log.file");
        } 
        catch(Exception e){
            System.out.println("error" + e);
        }    
    }

    static public PropInfo instance(){
        if(_instance == null){
            _instance = new PropInfo();
        }
        return _instance;
    }
}

主类:

try{
    PropInfo propinfo = PropInfo.instance();
    String connString = propinfo.executable + " " + propinfo.params1 + " " + 
            propinfo.filein + " " + propinfo.params2 + " " + " " + propinfo.log ;

    Runtime rt = Runtime.getRuntime();
    // Process pr = rt.exec 
    // (PropInfo.executable+" "+PropInfo.params1+" "+PropInfo.filein+" "
    //+PropInfo.params2+" "+PropInfo.log);
    Process pr = rt.exec(connString);

    BufferedReader input = new BufferedReader(new InputStreamReader (pr.getInputStream()));

    String line=null;
    StringBuffer start= new StringBuffer();
    while((line=input.readLine()) != null) {
        start.append("Started" + line + "\n");
        System.out.println(line);
    }

    // System.out.println("browse");

}
catch (Throwable t)  
{  
    t.printStackTrace();  
}  
finally 
{  
}

给出这个异常(exception):

errorjava.io.FileNotFoundException: Constants.properties (The system cannot find the  
file specified)
java.io.IOException: Cannot run program "null": CreateProcess error=2, The system  
cannot find the file specified
at java.lang.ProcessBuilder.start(ProcessBuilder.java:1042)
at java.lang.Runtime.exec(Runtime.java:615)
at java.lang.Runtime.exec(Runtime.java:448)
at java.lang.Runtime.exec(Runtime.java:345)
at com.emc.clp.license.StartTest.main(StartTest.java:44)
Caused by: java.io.IOException: CreateProcess error=2, The system cannot find the 
 file     specified
at java.lang.ProcessImpl.create(Native Method)
at java.lang.ProcessImpl.<init>(ProcessImpl.java:288)
at java.lang.ProcessImpl.start(ProcessImpl.java:133)
at java.lang.ProcessBuilder.start(ProcessBuilder.java:1023)
... 4 more

Answer 1

是的，不要将您的属性文件放入 src 文件夹中。把它放在你启动 jvm 的地方(或提供一个绝对路径)。另外，我真的建议去掉路径名中的正斜杠。

更新:添加这个以找出放置文件的位置:

System.out.println(new File(".").getAbsolutePath());