Package org.eclipse.jetty.util

Class SearchPattern

java.lang.Object
org.eclipse.jetty.util.SearchPattern
public class SearchPattern extends Object
SearchPattern Fast search for patterns within strings and arrays of bytes. Uses an implementation of the Boyer–Moore–Horspool algorithm with a 256 character alphabet. The algorithm has an average-case complexity of O(n) on random text and O(nm) in the worst case. where: m = pattern length n = length of data to search

  • Method Summary

    Modifier and Type
    Method
    Description
    static SearchPattern
    compile(byte[] pattern)
    Produces a SearchPattern instance which can be used to find matches of the pattern in data
    static SearchPattern
    compile(String pattern)
    Produces a SearchPattern instance which can be used to find matches of the pattern in data
    int
    endsWith(byte[] data, int offset, int length)
    Search for a partial match of the pattern at the end of the data.
    int
    getLength()
     
    int
    match(byte[] data, int offset, int length)
    Search for a complete match of the pattern within the data
    int
    startsWith(byte[] data, int offset, int length, int matched)
    Search for a possibly partial match of the pattern at the start of the data.

    Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

  • Method Details

    • compile

      public static SearchPattern compile(byte[] pattern)
      Produces a SearchPattern instance which can be used to find matches of the pattern in data
      Parameters:
      pattern - byte array containing the pattern
      Returns:
      a new SearchPattern instance using the given pattern

    • compile

      public static SearchPattern compile(String pattern)
      Produces a SearchPattern instance which can be used to find matches of the pattern in data
      Parameters:
      pattern - string containing the pattern
      Returns:
      a new SearchPattern instance using the given pattern

    • match

      public int match(byte[] data, int offset, int length)
      Search for a complete match of the pattern within the data
      Parameters:
      data - The data in which to search for. The data may be arbitrary binary data, but the pattern will always be StandardCharsets.US_ASCII encoded.
      offset - The offset within the data to start the search
      length - The length of the data to search
      Returns:
      The index within the data array at which the first instance of the pattern or -1 if not found

    • endsWith

      public int endsWith(byte[] data, int offset, int length)
      Search for a partial match of the pattern at the end of the data.
      Parameters:
      data - The data in which to search for. The data may be arbitrary binary data, but the pattern will always be StandardCharsets.US_ASCII encoded.
      offset - The offset within the data to start the search
      length - The length of the data to search
      Returns:
      the length of the partial pattern matched and 0 for no match.

    • startsWith

      public int startsWith(byte[] data, int offset, int length, int matched)
      Search for a possibly partial match of the pattern at the start of the data.
      Parameters:
      data - The data in which to search for. The data may be arbitrary binary data, but the pattern will always be StandardCharsets.US_ASCII encoded.
      offset - The offset within the data to start the search
      length - The length of the data to search
      matched - The length of the partial pattern already matched
      Returns:
      the length of the partial pattern matched and 0 for no match.

    • getLength

      public int getLength()
      Returns:
      The length of the pattern in bytes.