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public class Main {
private static int tokenNumber = 12;
private static int tokenLength = 12;
public static void main(String[] args) {
// declaration
StringBuilder chaineB = new StringBuilder();
Long[] resultIndexOfNatif = new Long[tokenNumber + 1];
Long[] resultIndexOf = new Long[tokenNumber + 1];
String[] str = new String[tokenNumber];
// generate chaine and str[]
for (int j = 0; j < tokenNumber; j++) {
str[j] = generateString(tokenLength);
chaineB.append(str[j]);
chaineB.append(" ");
}
System.out.println(chaineB);
String chaine = chaineB.toString();
// Chronometer IndexOfNatif
long top = System.currentTimeMillis();
for (int j = 0; j < tokenNumber; j++) {
long tmp = System.currentTimeMillis();
callIndexOfNatif(chaine, str[j]);
resultIndexOfNatif[j] = System.currentTimeMillis() - tmp;
}
resultIndexOfNatif[tokenNumber] = System.currentTimeMillis() - top;
// print result
System.out.println("Resultat IndexOfNatif : ");
for (int j = 0; j < tokenNumber + 1; j++) {
System.out.println(j + " : " + resultIndexOfNatif[j]);
}
// Chronometer IndexOf recodé
long top2 = System.currentTimeMillis();
for (int j = 0; j < tokenNumber; j++) {
long tmp = System.currentTimeMillis();
callIndexOf(chaine, str[j]);
resultIndexOf[j] = System.currentTimeMillis() - tmp;
}
resultIndexOf[tokenNumber] = System.currentTimeMillis() - top2;
// print result
System.out.println("Resultat IndexOf recodé : ");
for (int j = 0; j < tokenNumber + 1; j++) {
System.out.println(j + " : " + resultIndexOf[j]);
}
}
private static void callIndexOf(String chaine, String string) {
char[] x = chaine.toCharArray();
char[] y = string.toCharArray();
for (int i = 0; i < 10000000; i++) {
indexOf(x, y);
}
}
private static void callIndexOfNatif(String chaine, String string) {
for (int i = 0; i < 10000000; i++) {
chaine.indexOf(string);
}
}
public static int indexOf(char[] source, char[] str) {
return indexOf(source, str, 0);
}
public static int indexOf(char[] source, char[] str, int fromIndex) {
return indexOf(source, 0, source.length, str, 0, str.length, fromIndex);
}
static int indexOf(char[] source, int sourceOffset, int sourceCount,
char[] target, int targetOffset, int targetCount, int fromIndex) {
if (fromIndex >= sourceCount) {
return (targetCount == 0 ? sourceCount : -1);
}
if (fromIndex < 0) {
fromIndex = 0;
}
if (targetCount == 0) {
return fromIndex;
}
char first = target[targetOffset];
int max = sourceOffset + (sourceCount - targetCount);
for (int i = sourceOffset + fromIndex; i <= max; i++) {
/* Look for first character. */
if (source[i] != first) {
while (++i <= max && source[i] != first)
;
}
/* Found first character, now look at the rest of v2 */
if (i <= max) {
int j = i + 1;
int end = j + targetCount - 1;
for (int k = targetOffset + 1; j < end
&& source[j] == target[k]; j++, k++)
;
if (j == end) {
/* Found whole string. */
return i - sourceOffset;
}
}
}
return -1;
}
private static String chars = "abcdefghijklmnopqrstuvwxyz";
private static int charLength = chars.length();
public static String generateString(int length) {
StringBuilder pass = new StringBuilder(charLength);
for (int x = 0; x < length; x++) {
int i = (int) (Math.random() * charLength);
pass.append(chars.charAt(i));
}
return pass.toString();
}
} |
