fileToSTring不斷返回「」

Question

我設法讓這個代碼編譯出錯誤。但不知何故，它並沒有返回我在file1.txt和file.txt中寫入的字符串，我將它的路徑傳遞給str1和str2。我的目標是使用這個開源庫來測量包含在2個文本文件中的字符串之間的相似度。

在它的Javadoc內，其指出...

public static java.lang.StringBuffer fileToString(java.io.File f) 

private call to load a file and return its content as a string. 

Parameters: 
    f - a file for which to load its content 
Returns: 
    a string containing the files contents or "" if empty or not present 

這裏是我修改後的代碼試圖利用FileLoader功能，但未能歸還文件中的字符串。最終的結果不斷讓我回到「」。我不知道哪裏是我的錯：

package uk.ac.shef.wit.simmetrics; 
    import java.io.File; 
    import uk.ac.shef.wit.simmetrics.similaritymetrics.*; 
    import uk.ac.shef.wit.simmetrics.utils.*; 


public class SimpleExample { 
    public static void main(final String[] args) { 
    if(args.length != 2) { 

     usage(); 

    } else { 

     String str1 = "arg[0]"; 
     String str2 = "arg[1]"; 

     File objFile1 = new File(str1); 

     File objFile2 = new File(str2); 

     FileLoader obj1 = new FileLoader(); 
     FileLoader obj2 = new FileLoader(); 

     str1 = obj1.fileToString(objFile1).toString(); 

     str2 = obj2.fileToString(objFile2).toString(); 


     System.out.println(str1);    
     System.out.println(str2); 


     AbstractStringMetric metric = new MongeElkan(); 

     //this single line performs the similarity test 

     float result = metric.getSimilarity(str1, str2); 

     //outputs the results 

     outputResult(result, metric, str1, str2); 

    } 

} 


private static void outputResult(final float result, final AbstractStringMetric metric, final String str1, final String str2) { 

    System.out.println("Using Metric " + metric.getShortDescriptionString() + " on strings \"" + str1 + "\" & \"" + str2 + "\" gives a similarity score of " + result); 



} 



private static void usage() { 

    System.out.println("Performs a rudimentary string metric comparison from the arguments given.\n\tArgs:\n\t\t1) String1 to compare\n\t\t2)String2 to compare\n\n\tReturns:\n\t\tA standard output (command line of the similarity metric with the given test strings, for more details of this simple class please see the SimpleExample.java source file)"); 

} 

}

更新：我已經修改了代碼，但它給了我這個錯誤：

SimpleExample.java:79: cannot find symbol 
symbol : variable arg 
location: class uk.ac.shef.wit.simmetrics.SimpleExample 
     String str1 = arg[0]; 
        ^
SimpleExample.java:80: cannot find symbol 
symbol : variable arg 
location: class uk.ac.shef.wit.simmetrics.SimpleExample 
     String str2 = arg[1]; 
        ^

Answer 1

如果您正在運行Java程序通過命令行，似乎你沒有正確檢索參數，

String str1 = "arg[0]"; 
String str2 = "arg[1]"; 

應該是，

String str1 = args[0]; 
String str2 = args[1];