Having no result with Jlink function

Question

I'm new at Jlink (and English, so I'm sorry if things aren't clear).

I did a code which tries to scan a file searching for a given word. As a result, I'm supossed to get the line where the given word is found, but I get nothing in the notebook. Here's my code:

Needs["JLink`"]

Scanner[archivo_String, palabra_String] :=
    JavaBlock[
  Module[{entrada, conteolin = 0, conteopal = 0, sc, ruta, leer, lin, 
    st},
   InstallJava[];

   ruta = JavaNew["java.io.File", archivo];
   sc = JavaNew["java.util.Scanner", palabra];

   entrada = JavaNew["java.io.FileReader", ruta];
   leer = JavaNew["java.io.BufferedReader", entrada];

   lin = leer@readLine[];


   While[lin != Null, st = JavaNew["java.util.StringTokenizer", lin];

    conteolin = conteolin + 1;

        While[st@hasMoreTokens[],

      If[st@NextToken[]@equalsIgnoreCase[sc], conteopal++, 

       Print[sc <> "aparece en la linea" <> conteolin]];

      lin = leer@readLine[];
      ]

     If[conteopal > 0, 
      Print["La palabra" <> sc <> "aparece" <> conteopal <> "veces", 
       "no se econtró la palabara"]]
    ];
   ]
  ]

I don´t know if I wrote it wrong, the Jlink docs has info about the Modal and Modeless interaction, do I have to use one of them?

Thank you

Answer 1

Needs["JLink`"]

       Scanner[archivo_String, palabra_String] := JavaBlock @ 
         Module[{entrada, conteolin, conteopal, sc, ruta, leer, lin, st},
         conteopal = conteolin = 0; lin = "";
         ReinstallJava[];
         ruta = JavaNew["java.io.File", archivo];
         entrada = JavaNew["java.io.FileReader", ruta];
         leer = JavaNew["java.io.BufferedReader", entrada(*,8*1024*)];
         lin = leer @ readLine[];
         While[ lin =!= Null
            ,
              lin = leer @ readLine[] 
              ; If[! StringQ[lin], Break[]]
              ; conteolin = conteolin + 1
              ; st = JavaNew["java.util.StringTokenizer", lin] 
              ; While[st @ hasMoreTokens[]
                 , proximaToken = st @ nextToken[]
                 ; 
         If[JavaNew["java.lang.String", proximaToken] @ 
           equalsIgnoreCase[palabra]
                      , conteopal++
                      ; 
          Print["La palabra " <> palabra <> " aparece en la linea " <> 
            ToString[conteolin]]
                    ]
                 ] 
          ]
         ; If[conteopal > 0
             , Print @ Row[{"La palabra \"", palabra, "\" aparece ", conteopal
                               , If[conteopal == 1, " vez", " veces"]
                               }
                       ]
             , Print[ "no se encontró la palabara " <> palabra ]
           ]
]

file = FindFile["ExampleData/USConstitution.txt"];
Scanner[file, "Qualification"] // AbsoluteTiming

works, but is really rather slow, somehow, maybe because of the rather slow JLink overhead. So I would either code the logic completely in Java, or, just do something like

AbsoluteTiming[
 lins = Import[file, "Lines"];
 wlins = ImportString[#, "Words"] & /@ lins;
 {Position[wlins, "Qualification"][[All, 1]],
  Count[wlins, "Qualification", -1]}
 ]

which finishes in less than one second, about 20 times faster ...