Wofür wird dieser Parameter verwendet?

Question

Hauptklasse:

import java.util.ArrayList; 

public class readingfiles { 
public static void main (String args[]) 
{ 
     ArrayList<Double> result2 = lol2016.ReadNumberFile("lel"); 
     System.out.println("Result 2: " + result2); 
} 
} 

Unabhängig davon, was ich für diese in der Parametereingabe, ändert sich nichts ??

ArrayList Ergebnis2 = lol2016.ReadNumberFile ("lel");

import java.util.*; 
import java.io.*; 
public class lol2016 
{ 
static public ArrayList<Double> ReadNumberFile(String filename) 
{ 
    ArrayList<Double> res = new ArrayList<Double>(); 
    Reader r; 
    try 
    { 
     r = new BufferedReader(new FileReader("C:\\Users\\Documents\\Primes.txt")); 
     StreamTokenizer stok = new StreamTokenizer(r); 
     stok.parseNumbers(); 
     stok.nextToken(); 
     while (stok.ttype != StreamTokenizer.TT_EOF) 
     { 
      if (stok.ttype == StreamTokenizer.TT_NUMBER) 
      { 
       res.add(stok.nval); 
      } 
      stok.nextToken(); 
     } 
    } 
    catch(Exception E) 
    { 
     System.out.println("+++ReadFile: "+E.getMessage()); 
    } 
    return(res); 
} 
} 

Der Ausgang bleibt gleich, unabhängig von dem, was ich zwischen diesen Parameter setzen, ist meine Frage, was soll es gehen? Übrigens ist dies Teil eines viel größeren Projekts, aber ich glaube, dass dies genug Code ist, um mir zu helfen, zu verstehen, was ich in jene Parameter schreiben könnte, die meine Ausgabe beeinflussen würden.

Ausgang:

Result 2: [2.0, 3.0, 5.0, 7.0, 11.0, 13.0, 17.0, 19.0, 23.0, 29.0, 31.0, 37.0, 41.0, 43.0, 47.0, 53.0, 59.0, 61.0, 67.0, 71.0, 73.0, 79.0, 83.0, 89.0, 97.0, 101.0, 103.0, 107.0, 109.0, 113.0, 127.0, 131.0, 137.0, 139.0, 149.0, 151.0, 157.0, 163.0, 167.0, 173.0, 179.0, 181.0, 191.0, 193.0, 197.0, 199.0, 211.0, 223.0, 227.0, 229.0, 233.0, 239.0, 241.0, 251.0, 257.0, 263.0, 269.0, 271.0, 277.0, 281.0, 283.0, 293.0, 307.0, 311.0, 313.0, 317.0, 331.0, 337.0, 347.0, 349.0, 353.0, 359.0, 367.0, 373.0, 379.0, 383.0, 389.0, 397.0, 401.0, 409.0, 419.0, 421.0, 431.0, 433.0, 439.0, 443.0, 449.0, 457.0, 461.0, 463.0, 467.0, 479.0, 487.0, 491.0, 499.0, 503.0, 509.0, 521.0, 523.0, 541.0, 547.0, 557.0, 563.0, 569.0, 571.0, 577.0, 587.0, 593.0, 599.0, 601.0, 607.0, 613.0, 617.0, 619.0, 631.0, 641.0, 643.0, 647.0, 653.0, 659.0, 661.0, 673.0, 677.0, 683.0, 691.0, 701.0, 709.0, 719.0, 727.0, 733.0, 739.0, 743.0, 751.0, 757.0, 761.0, 769.0, 773.0, 787.0, 797.0, 809.0, 811.0, 821.0, 823.0, 827.0, 829.0, 839.0, 853.0, 857.0, 859.0, 863.0, 877.0, 881.0, 883.0, 887.0, 907.0, 911.0, 919.0, 929.0, 937.0, 941.0, 947.0, 953.0, 967.0, 971.0, 977.0, 983.0, 991.0, 997.0, 1009.0, 1013.0, 1019.0, 1021.0, 1031.0, 1033.0, 1039.0, 1049.0, 1051.0, 1061.0, 1063.0, 1069.0, 1087.0, 1091.0, 1093.0, 1097.0, 1103.0, 1109.0, 1117.0, 1123.0, 1129.0, 1151.0, 1153.0, 1163.0, 1171.0, 1181.0, 1187.0, 1193.0, 1201.0, 1213.0, 1217.0, 1223.0, 1229.0, 1231.0, 1237.0, 1249.0, 1259.0, 1277.0, 1279.0, 1283.0, 1289.0, 1291.0, 1297.0, 1301.0, 1303.0, 1307.0, 1319.0, 1321.0, 1327.0, 1361.0, 1367.0, 1373.0, 1381.0, 1399.0, 1409.0, 1423.0, 1427.0, 1429.0, 1433.0, 1439.0, 1447.0, 1451.0, 1453.0, 1459.0, 1471.0, 1481.0, 1483.0, 1487.0, 1489.0, 1493.0, 1499.0, 1511.0, 1523.0, 1531.0, 1543.0, 1549.0, 1553.0, 1559.0, 1567.0, 1571.0, 1579.0, 1583.0, 1597.0, 1601.0, 1607.0, 1609.0, 1613.0, 1619.0, 1621.0, 1627.0, 1637.0, 1657.0, 1663.0, 1667.0, 1669.0, 1693.0, 1697.0, 1699.0, 1709.0, 1721.0, 1723.0, 1733.0, 1741.0, 1747.0, 1753.0, 1759.0, 1777.0, 1783.0, 1787.0, 1789.0, 1801.0, 1811.0, 1823.0, 1831.0, 1847.0, 1861.0, 1867.0, 1871.0, 1873.0, 1877.0, 1879.0, 1889.0, 1901.0, 1907.0, 1913.0, 1931.0, 1933.0, 1949.0, 1951.0, 1973.0, 1979.0, 1987.0, 1993.0, 1997.0, 1999.0, 2003.0, 2011.0, 2017.0, 2027.0, 2029.0, 2039.0, 2053.0, 2063.0, 2069.0, 2081.0, 2083.0, 2087.0, 2089.0, 2099.0, 2111.0, 2113.0, 2129.0, 2131.0, 2137.0, 2141.0, 2143.0, 2153.0, 2161.0, 2179.0, 2203.0, 2207.0, 2213.0, 2221.0, 2237.0, 2239.0, 2243.0, 2251.0, 2267.0, 2269.0, 2273.0, 2281.0, 2287.0, 2293.0, 2297.0, 2309.0, 2311.0, 2333.0, 2339.0, 2341.0, 2347.0, 2351.0, 2357.0, 2371.0, 2377.0, 2381.0, 2383.0, 2389.0, 2393.0, 2399.0, 2411.0, 2417.0, 2423.0, 2437.0, 2441.0, 2447.0, 2459.0, 2467.0, 2473.0, 2477.0, 2503.0, 2521.0, 2531.0, 2539.0, 2543.0, 2549.0, 2551.0, 2557.0, 2579.0, 2591.0, 2593.0, 2609.0, 2617.0, 2621.0, 2633.0, 2647.0, 2657.0, 2659.0, 2663.0, 2671.0, 2677.0, 2683.0, 2687.0, 2689.0, 2693.0, 2699.0, 2707.0, 2711.0, 2713.0, 2719.0, 2729.0, 2731.0, 2741.0, 2749.0, 2753.0, 2767.0, 2777.0, 2789.0, 2791.0, 2797.0, 2801.0, 2803.0, 2819.0, 2833.0, 2837.0, 2843.0, 2851.0, 2857.0, 2861.0, 2879.0, 2887.0, 2897.0, 2903.0, 2909.0, 2917.0, 2927.0, 2939.0, 2953.0, 2957.0, 2963.0, 2969.0, 2971.0, 2999.0, 3001.0, 3011.0, 3019.0, 3023.0, 3037.0, 3041.0, 3049.0, 3061.0, 3067.0, 3079.0, 3083.0, 3089.0, 3109.0, 3119.0, 3121.0, 3137.0, 3163.0, 3167.0, 3169.0, 3181.0, 3187.0, 3191.0, 3203.0, 3209.0, 3217.0, 3221.0, 3229.0, 3251.0, 3253.0, 3257.0, 3259.0, 3271.0, 3299.0, 3301.0, 3307.0, 3313.0, 3319.0, 3323.0, 3329.0, 3331.0, 3343.0, 3347.0, 3359.0, 3361.0, 3371.0, 3373.0, 3389.0, 3391.0, 3407.0, 3413.0, 3433.0, 3449.0, 3457.0, 3461.0, 3463.0, 3467.0, 3469.0, 3491.0, 3499.0, 3511.0, 3517.0, 3527.0, 3529.0, 3533.0, 3539.0, 3541.0, 3547.0, 3557.0, 3559.0, 3571.0, 3581.0, 3583.0, 3593.0, 3607.0, 3613.0, 3617.0, 3623.0, 3631.0, 3637.0, 3643.0, 3659.0, 3671.0, 3673.0, 3677.0, 3691.0, 3697.0, 3701.0, 3709.0, 3719.0, 3727.0, 3733.0, 3739.0, 3761.0, 3767.0, 3769.0, 3779.0, 3793.0, 3797.0, 3803.0, 3821.0, 3823.0, 3833.0, 3847.0, 3851.0, 3853.0, 3863.0, 3877.0, 3881.0, 3889.0, 3907.0, 3911.0, 3917.0, 3919.0, 3923.0, 3929.0, 3931.0, 3943.0, 3947.0, 3967.0, 3989.0, 4001.0, 4003.0, 4007.0, 4013.0, 4019.0, 4021.0, 4027.0, 4049.0, 4051.0, 4057.0, 4073.0, 4079.0, 4091.0, 4093.0, 4099.0, 4111.0, 4127.0, 4129.0, 4133.0, 4139.0, 4153.0, 4157.0, 4159.0, 4177.0, 4201.0, 4211.0, 4217.0, 4219.0, 4229.0, 4231.0, 4241.0, 4243.0, 4253.0, 4259.0, 4261.0, 4271.0, 4273.0, 4283.0, 4289.0, 4297.0, 4327.0, 4337.0, 4339.0, 4349.0, 4357.0, 4363.0, 4373.0, 4391.0, 4397.0, 4409.0, 4421.0, 4423.0, 4441.0, 4447.0, 4451.0, 4457.0, 4463.0, 4481.0, 4483.0, 4493.0, 4507.0, 4513.0, 4517.0, 4519.0, 4523.0, 4547.0, 4549.0, 4561.0, 4567.0, 4583.0, 4591.0, 4597.0, 4603.0, 4621.0, 4637.0, 4639.0, 4643.0, 4649.0, 4651.0, 4657.0, 4663.0, 4673.0, 4679.0, 4691.0, 4703.0, 4721.0, 4723.0, 4729.0, 4733.0, 4751.0, 4759.0, 4783.0, 4787.0, 4789.0, 4793.0, 4799.0, 4801.0, 4813.0, 4817.0, 4831.0, 4861.0, 4871.0, 4877.0, 4889.0, 4903.0, 4909.0, 4919.0, 4931.0, 4933.0, 4937.0, 4943.0, 4951.0, 4957.0, 4967.0, 4969.0, 4973.0, 4987.0, 4993.0, 4999.0, 5003.0, 5009.0, 5011.0, 5021.0, 5023.0, 5039.0, 5051.0, 5059.0, 5077.0, 5081.0, 5087.0, 5099.0, 5101.0, 5107.0, 5113.0, 5119.0, 5147.0, 5153.0, 5167.0, 5171.0, 5179.0, 5189.0, 5197.0, 5209.0, 5227.0, 5231.0, 5233.0, 5237.0, 5261.0, 5273.0, 5279.0, 5281.0, 5297.0, 5303.0, 5309.0, 5323.0, 5333.0, 5347.0, 5351.0, 5381.0, 5387.0, 5393.0, 5399.0, 5407.0, 5413.0, 5417.0, 5419.0, 5431.0, 5437.0, 5441.0, 5443.0, 5449.0, 5471.0, 5477.0, 5479.0, 5483.0, 5501.0, 5503.0, 5507.0, 5519.0, 5521.0, 5527.0, 5531.0, 5557.0, 5563.0, 5569.0, 5573.0, 5581.0, 5591.0, 5623.0, 5639.0, 5641.0, 5647.0, 5651.0, 5653.0, 5657.0, 5659.0, 5669.0, 5683.0, 5689.0, 5693.0, 5701.0, 5711.0, 5717.0, 5737.0, 5741.0, 5743.0, 5749.0, 5779.0, 5783.0, 5791.0, 5801.0, 5807.0, 5813.0, 5821.0, 5827.0, 5839.0, 5843.0, 5849.0, 5851.0, 5857.0, 5861.0, 5867.0, 5869.0, 5879.0, 5881.0, 5897.0, 5903.0, 5923.0, 5927.0, 5939.0, 5953.0, 5981.0, 5987.0, 6007.0, 6011.0, 6029.0, 6037.0, 6043.0, 6047.0, 6053.0, 6067.0, 6073.0, 6079.0, 6089.0, 6091.0, 6101.0, 6113.0, 6121.0, 6131.0, 6133.0, 6143.0, 6151.0, 6163.0, 6173.0, 6197.0, 6199.0, 6203.0, 6211.0, 6217.0, 6221.0, 6229.0, 6247.0, 6257.0, 6263.0, 6269.0, 6271.0, 6277.0, 6287.0, 6299.0, 6301.0, 6311.0, 6317.0, 6323.0, 6329.0, 6337.0, 6343.0, 6353.0, 6359.0, 6361.0, 6367.0, 6373.0, 6379.0, 6389.0, 6397.0, 6421.0, 6427.0, 6449.0, 6451.0, 6469.0, 6473.0, 6481.0, 6491.0, 6521.0, 6529.0, 6547.0, 6551.0, 6553.0, 6563.0, 6569.0, 6571.0, 6577.0, 6581.0, 6599.0, 6607.0, 6619.0, 6637.0, 6653.0, 6659.0, 6661.0, 6673.0, 6679.0, 6689.0, 6691.0, 6701.0, 6703.0, 6709.0, 6719.0, 6733.0, 6737.0, 6761.0, 6763.0, 6779.0, 6781.0, 6791.0, 6793.0, 6803.0, 6823.0, 6827.0, 6829.0, 6833.0, 6841.0, 6857.0, 6863.0, 6869.0, 6871.0, 6883.0, 6899.0, 6907.0, 6911.0, 6917.0, 6947.0, 6949.0, 6959.0, 6961.0, 6967.0, 6971.0, 6977.0, 6983.0, 6991.0, 6997.0, 7001.0, 7013.0, 7019.0, 7027.0, 7039.0, 7043.0, 7057.0, 7069.0, 7079.0, 7103.0, 7109.0, 7121.0, 7127.0, 7129.0, 7151.0, 7159.0, 7177.0, 7187.0, 7193.0, 7207.0, 7211.0, 7213.0, 7219.0, 7229.0, 7237.0, 7243.0, 7247.0, 7253.0, 7283.0, 7297.0, 7307.0, 7309.0, 7321.0, 7331.0, 7333.0, 7349.0, 7351.0, 7369.0, 7393.0, 7411.0, 7417.0, 7433.0, 7451.0, 7457.0, 7459.0, 7477.0, 7481.0, 7487.0, 7489.0, 7499.0, 7507.0, 7517.0, 7523.0, 7529.0, 7537.0, 7541.0, 7547.0, 7549.0, 7559.0, 7561.0, 7573.0, 7577.0, 7583.0, 7589.0, 7591.0, 7603.0, 7607.0, 7621.0, 7639.0, 7643.0, 7649.0, 7669.0, 7673.0, 7681.0, 7687.0, 7691.0, 7699.0, 7703.0, 7717.0, 7723.0, 7727.0, 7741.0, 7753.0, 7757.0, 7759.0, 7789.0, 7793.0, 7817.0, 7823.0, 7829.0, 7841.0, 7853.0, 7867.0, 7873.0, 7877.0, 7879.0, 7883.0, 7901.0, 7907.0, 7919.0] 

Bare in meiner Textdatei, die buchstäblich nur die Primzahlen alle zeigt gelesen wird gleich der Ausgabe.

Answer 1

Unabhängig davon, was ich in den Parameter dafür eingeben, ändert sich nichts ??

Es ist, weil das filename Argument nicht überall in der ReadNumberFile(String filename) Methode verwendet wird ..

Wie es scheint, wird dieser Parameter (filename) steht für den Namen (oder vielleicht der vollständig qualifizierte Pfad) eine Datei, die sollte gelesen werden. Wenn das der Fall ist, sollten Sie diese Zeile ändern in:

r = new BufferedReader(new FileReader(filename));