java 字节序列_使用Java在二进制文件中搜索字节序列
小编典典
不，没有内置方法可以做到这一点。但是，直接从此处复制(对原始代码有两个修复)：
/**
* Knuth-Morris-Pratt Algorithm for Pattern Matching
*/
class KMPMatch {
/**
* Finds the first occurrence of the pattern in the text.
*/
public static int indexOf(byte[] data, byte[] pattern) {
if (data.length == 0) return -1;
int[] failure = computeFailure(pattern);
int j = 0;
for (int i = 0; i < data.length; i++) {
while (j > 0 && pattern[j] != data[i]) {
j = failure[j - 1];
}
if (pattern[j] == data[i]) { j++; }
if (j == pattern.length) {
return i - pattern.length + 1;
}
}
return -1;
}
/**
* Computes the failure function using a boot-strapping process,
* where the pattern is matched against itself.
*/
private static int[] computeFailure(byte[] pattern) {
int[] failure = new int[pattern.length];
int j = 0;
for (int i = 1; i < pattern.length; i++) {
while (j > 0 && pattern[j] != pattern[i]) {
j = failure[j - 1];
}
if (pattern[j] == pattern[i]) {
j++;
}
failure[i] = j;
}
return failure;
}
}
2020-09-16
小编典典 不，没有内置方法可以做到这一点。但是，直接从此处复制(对原始代码有两个修复)： /** * Knuth-Morris-Pratt Algorithm for Pattern Matching */ class KMPMatch { /** * Finds the first occurrence of the pattern in the text. */ public static int indexOf(byte[] data, byte[] pattern) { if (data.length == 0) return -1; int[] failure = computeFailure(pattern); int j = 0; for (int i = 0; i < data.length; i++) { while (j > 0 && pattern[j] != data[i]) { j = failure[j - 1]; } if (pattern[j] == data[i]) { j++; } if (j == pattern.length) { return i - pattern.length + 1; } } return -1; } /** * Computes the failure function using a boot-strapping process, * where the pattern is matched against itself. */ private static int[] computeFailure(byte[] pattern) { int[] failure = new int[pattern.length]; int j = 0; for (int i = 1; i < pattern.length; i++) { while (j > 0 && pattern[j] != pattern[i]) { j = failure[j - 1]; } if (pattern[j] == pattern[i]) { j++; } failure[i] = j; } return failure; } } 2020-09-16