Why do I get garbage output when printing an int[]?
My program is suppose to count the occurrence of each character in a file ignoring upper and lower case. The method I wrote is:
public int[] getCharTimes(File textFile) throws FileNotFoundException {
Scanner inFile = new Scanner(textFile);
int[] lower = new int[26];
char current;
int other = 0;
while(inFile.hasNext()){
String line = inFile.nextLine();
String line2 = line.toLowerCase();
for (int ch = 0; ch < line2.length(); ch++) {
current = line2.charAt(ch);
if(current >= 'a' && current <= 'z')
lower[current-'a']++;
else
other++;
}
}
return lower;
}
And is printed out using:
for(int letter = 0; letter < 26; letter++) {
System.out.print((char) (letter + 'a'));
System.out.println(": " + ts.getCharTimes(file));
}
Where ts is a TextStatistic
object created earlier in my main method. However when I run my program, instead of printing out the number of how often the character occurs it prints:
a: [I@f84386
b: [I@1194a4e
c: [I@15d56d5
d: [I@efd552
e: [I@开发者_运维问答19dfbff
f: [I@10b4b2f
And I don't know what I'm doing wrong.
Check out the signature of your method; it is returning an array of ints.
ts.getCharTimes(file) returns int array. So to print use:
ts.getCharTimes(file)[letter]
You are also running the method 26 times, which is likely to be wrong. Since the call context (parameters and such) is not affected by the iterations of the loop consider changing the code to:
int[] letterCount = ts.getCharTimes(file);
for(int letter = 0; letter < 26; letter++) {
System.out.print((char) (letter + 'a'));
System.out.println(": " + letterCount[letter]);
}
ts.getCharTimes(file) returns int array.
print ts.getCharTimes(file)[letter]
It's not garbage; it's a feature!
public static void main(String[] args) {
System.out.println(args);
System.out.println("long: " + new long[0]);
System.out.println("int: " + new int[0]);
System.out.println("short: " + new short[0]);
System.out.println("byte: " + new byte[0]);
System.out.println("float: " + new float[0]);
System.out.println("double: " + new double[0]);
System.out.println("boolean: " + new boolean[0]);
System.out.println("char: " + new char[0]);
}
[Ljava.lang.String;@70922804 long: [J@b815859 int: [I@58cf40f5 short: [S@eb1c260 byte: [B@38503429 float: [F@19908ca1 double: [D@6100ab23 boolean: [Z@72e3b895 char: [C@446b7920
"The classes for arrays have strange names that are not valid identifiers;"—The Java Virtual Machine Specification.
Addendum: See also toString()
.
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