Relatively long and floating

Question

Relatively long and floating

i developed the code below

static String m(float i) {
    return "float";
}

static String m(double i) {
    return "double";
}

public static void main(String[] args) {
    int a1 = 1;
    long b1 = 2;
    System.out.print(m(a1) + "," + m(b1));
}

Both results print float, float, what is the reason for this, please report and how can I call twice, please report thanks.

+3

java

dghtr Apr 29 '12 at 5:39

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4 answers

The short answer: Java can automatically expand intand longup float, and doubles, but Java will choose an extension floatbecause it is smaller (in terms of memory) than double. You can invoke the method version of a doublemethod by explicitly passing an argument:

System.out.print(m((double)a1) + "," + m((double)b1));

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short    2 bytes
char     2 bytes
int      4 bytes
float    4 bytes
long     8 bytes
double   8 bytes

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public static void foo(float f) {
    System.out.println(f);
}

public static void main(String[] args) {
    int a = 123;
    int b = 1234567890;
    foo(a);
    foo(b);
}

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