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
  • Match everything enclosed
    (?:...)
  • Capture everything enclosed
    (...)
  • 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

/
/
g

Test String

Substitution

Processing...

Code Generator

Generated Code

$re = '/assertEquals\(([^,]+),\s(.+)\);/'; $str = 'package com.gdit.fwa.informant.model.definitions; import static org.junit.Assert.assertEquals; import org.junit.Test; import com.gdit.fwa.informant.model.base.definition.RelationalOperator; import com.gdit.fwa.informant.model.base.definition.SqlConstants; @SuppressWarnings("static-method") public class RelationalOperatorTest { @Test public void testGetRelOperatorSql() { assertEquals(RelationalOperator.DEFAULT.getRelOperatorSql(), ""); assertEquals(RelationalOperator.IS.getRelOperatorSql(), "IS"); assertEquals(RelationalOperator.IS_NOT.getRelOperatorSql(), "IS NOT"); assertEquals(RelationalOperator.EQUAL.getRelOperatorSql(), "="); assertEquals(RelationalOperator.NOT_EQUAL.getRelOperatorSql(), "<>"); assertEquals(RelationalOperator.GREATER_THAN.getRelOperatorSql(), ">"); assertEquals(RelationalOperator.LESS_THAN.getRelOperatorSql(), "<"); assertEquals(RelationalOperator.GREATER_EQUAL.getRelOperatorSql(), ">="); assertEquals(RelationalOperator.LESS_EQUAL.getRelOperatorSql(), "<="); assertEquals(RelationalOperator.BETWEEN.getRelOperatorSql(), "BETWEEN"); assertEquals(RelationalOperator.IN.getRelOperatorSql(), "IN"); assertEquals(RelationalOperator.NOT_IN.getRelOperatorSql(), "NOT IN"); assertEquals(RelationalOperator.LIKE.getRelOperatorSql(), "LIKE"); assertEquals(RelationalOperator.NOT_LIKE.getRelOperatorSql(), "NOT LIKE"); assertEquals(RelationalOperator.SOUNDS_LIKE.getRelOperatorSql(), "SOUNDS LIKE"); } @Test public void testGetRelationalOperator() { assertEquals(RelationalOperator.DEFAULT, RelationalOperator.getRelationalOperator("")); assertEquals(RelationalOperator.IS, RelationalOperator.getRelationalOperator("IS")); assertEquals(RelationalOperator.IS_NOT, RelationalOperator.getRelationalOperator("IS NOT")); assertEquals(RelationalOperator.EQUAL, RelationalOperator.getRelationalOperator("=")); assertEquals(RelationalOperator.NOT_EQUAL, RelationalOperator.getRelationalOperator("<>")); assertEquals(RelationalOperator.GREATER_THAN, RelationalOperator.getRelationalOperator(">")); assertEquals(RelationalOperator.LESS_THAN, RelationalOperator.getRelationalOperator("<")); assertEquals(RelationalOperator.GREATER_EQUAL, RelationalOperator.getRelationalOperator(">=")); assertEquals(RelationalOperator.LESS_EQUAL, RelationalOperator.getRelationalOperator("<=")); assertEquals(RelationalOperator.BETWEEN, RelationalOperator.getRelationalOperator("BETWEEN")); assertEquals(RelationalOperator.IN, RelationalOperator.getRelationalOperator("IN")); assertEquals(RelationalOperator.NOT_IN, RelationalOperator.getRelationalOperator("NOT IN")); assertEquals(RelationalOperator.LIKE, RelationalOperator.getRelationalOperator("LIKE")); assertEquals(RelationalOperator.NOT_LIKE, RelationalOperator.getRelationalOperator("NOT LIKE")); assertEquals(RelationalOperator.SOUNDS_LIKE, RelationalOperator.getRelationalOperator("SOUNDS LIKE")); } @Test public void testRelOpEqualityFunctions() { for (RelationalOperator relOp : RelationalOperator.values()) { if (relOp == RelationalOperator.IS || relOp == RelationalOperator.IS_NOT){ assertEquals(relOp.isEquality(), true); assertEquals(relOp.getNullLogicOperator(), SqlConstants.OR); assertEquals(relOp.getNullRelOperator(), RelationalOperator.IS); assertEquals(relOp.getRelOperatorFilterSql(), RelationalOperator.IN.getRelOperatorSql()); } else { assertEquals(relOp.isEquality(), false); assertEquals(relOp.getNullLogicOperator(), SqlConstants.AND); assertEquals(relOp.getNullRelOperator(), RelationalOperator.IS_NOT); assertEquals(relOp.getRelOperatorFilterSql(), RelationalOperator.NOT_IN.getRelOperatorSql()); } } } @Test @SuppressWarnings("deprecation") public void testGetNullValue() { assertEquals(RelationalOperator.getNullValue(), SqlConstants.NULL); } @Test public void testGetNullClause() { for (RelationalOperator relOp : RelationalOperator.values()) { switch (relOp) { case IS: case EQUAL: assertEquals(relOp.getNullClause("Test"), " OR Test IS null"); break; case IS_NOT: case NOT_EQUAL: assertEquals(relOp.getNullClause("Test"), " AND Test IS NOT null"); break; default: assertEquals(relOp.getNullClause("Test"), ""); } } } } '; $subst = "assertEquals\($2\, $1\);"; $result = preg_replace($re, $subst, $str); echo "The result of the substitution is ".$result;

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 PHP, please visit: http://php.net/manual/en/ref.pcre.php