【java】字符串查找

/**
* 查找text内是否包含pattern
* @param text
* @param pattern
* @return -1 if 不包含；位置 if 包含。
* kmp 见//http://www.cnblogs.com/c-cloud/p/3224788.html
*/
public static int strstr(String text, String pattern){
if (text == null || pattern == null) {
return -1;
}
char []textArray = text.toCharArray();
char []patternArray = pattern.toCharArray();
int textLen = text.length();
int patternLen = pattern.length();
int loopSize = textLen - patternLen;
for(int i = 0; i <= loopSize; i++){
boolean isBreak = false;
for(int j = 0; j < patternLen; j++){
if (textArray[j + i] != patternArray[j]) {
isBreak = true;
break;
}
}
if (!isBreak) {
return i;
}
}
return -1;
}