Regular Expressions 101

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An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
  • Flags/Modifiers
  • Substitution
  • A single character of: a, b or c
    [abc]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Non-capturing group
    (?:...)
  • Capturing group
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression
Processing...

Test String

Code Generator

Language

Generated Code

import re regex = re.compile(r"(interface [a-zA-Z0-9 <>,\.\/*?[\s]]* \{|(@Immutable|@ThreadSafe|@NotThreadSafe)(.*[\n])*.*(class|enum) [a-zA-Z0-9\s<>,\.\/*?]* \{)") test_str = ("package de.invesdwin.common.persistence.jpa.api.dao;\n\n" "import java.io.Serializable;\n" "import java.lang.reflect.Field;\n" "import java.util.ArrayList;\n" "import java.util.List;\n\n" "import javax.annotation.concurrent.ThreadSafe;\n" "import javax.persistence.ElementCollection;\n" "import javax.persistence.Embedded;\n" "import javax.persistence.Query;\n" "import javax.persistence.TypedQuery;\n\n" "import org.apache.commons.lang3.mutable.MutableBoolean;\n" "import org.springframework.data.domain.Page;\n" "import org.springframework.data.domain.Pageable;\n" "import org.springframework.data.domain.Sort;\n" "import org.springframework.data.jpa.repository.support.SimpleJpaRepository;\n" "import org.springframework.transaction.annotation.Transactional;\n" "import org.springframework.util.ReflectionUtils.FieldCallback;\n\n" "import de.invesdwin.common.lang.Assertions;\n" "import de.invesdwin.common.lang.Reflections;\n" "import de.invesdwin.common.persistence.jpa.PersistenceProperties;\n" "import de.invesdwin.common.persistence.jpa.api.query.QueryConfig;\n\n" "/**\n" " * A DAO (DataAccessObject) is a special Repository that works for only one Entity. It implements default\n" " * CRUD-Operations for it.\n" " * \n" " * JPA Entity attached/detaches status is automatically handled, so you don't need to care about that.\n" " * \n" " * @author subes\n" " */\n" "@ThreadSafe\n" "public abstract class ACustomIdDao<E, PK extends Serializable> extends ARepository implements IDao<E, PK> {\n\n" " private final Class<E> genericType;\n" " private final boolean deleteInBatchSupported;\n" " private final QueryByExampleHelper<E, PK> queryByExampleHelper;\n" " private Integer connectionBatchSize;\n" " private SimpleJpaRepository<E, PK> delegate;\n" " private String persistenceUnitName;\n\n" "}\n") match = regex.search(test_str) if match: print(f"Match was found at {match.start()}-{match.end()}: {match.group()}") for group_num, group in enumerate(match.groups(), start=1): print(f"Group {group_num} found at {match.start(group_num)}-{match.end(group_num)}: {group}")

Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Python, please visit: https://docs.python.org/3/library/re.html