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
No Match

/
/
igU

Test String

Code Generator

Language

Generated Code

import java.util.regex.Matcher; import java.util.regex.Pattern; public class Example { public static void main(String[] args) { final String regex = "(?<prm>\\w+)\\s+.*:\\s*=\\s*'(?<tbl>\\w+)'\\s*;(?:.|\\n)*(?:alter|create)\\s+table\\s+'\\s*\\|\\|\\s*(\\k<prm>\\s+)"; final String string = "DECLARE\n" + "COUNTER NUMBER(10) := 0;\n" + "pTABLENAME VARCHAR2(100) := 'ALM_AL1';\n" + "pCOLUMNNAME VARCHAR2(100) := 'FLOATACCRUALDCBASISDAYC';\n" + "pDATATYPE VARCHAR2(100) := 'NVARCHAR2(50) NULL';\n" + "pSQL VARCHAR2(32000) := '\n" + "ALTER TABLE ' || pTABLENAME || ' ADD ' || pCOLUMNNAME || ' ' || pDATATYPE;\n" + "BEGIN\n" + " SELECT COUNT(0) INTO COUNTER FROM USER_TAB_COLUMNS WHERE TABLE_NAME=UPPER(pTABLENAME) AND COLUMN_NAME=UPPER(pCOLUMNNAME);\n" + " IF COUNTER>0 THEN\n" + " dbms_output.put_line(pTABLENAME || ' tablosunda ' || pCOLUMNNAME || ' kolonu var.');\n" + " ELSE\n" + " EXECUTE IMMEDIATE pSQL;\n" + " dbms_output.put_line(pTABLENAME || ' tablosuna' || pCOLUMNNAME || ' kolonu oluÅ?turuldu.');\n" + " END IF;\n" + " \n" + " EXCEPTION\n" + " WHEN OTHERS THEN\n" + " dbms_output.put_line('HATA: ' || pSQL || ' -> SQLERRM: ' || SQLERRM);\n" + "END;\n" + "/\n\n" + "DECLARE\n" + "COUNTER NUMBER(10) := 0;\n" + "pTABLENAME VARCHAR2(100) := 'ALM_AL2';\n" + "pCOLUMNNAME VARCHAR2(100) := 'RATETYPETYPE';\n" + "pDATATYPE VARCHAR2(100) := 'NVARCHAR2(40) NULL';\n" + "pSQL VARCHAR2(32000) := '\n" + "ALTER TABLE ' || pTABLENAME || ' ADD ' || pCOLUMNNAME || ' ' || pDATATYPE;\n" + "BEGIN\n" + " SELECT COUNT(0) INTO COUNTER FROM USER_TAB_COLUMNS WHERE TABLE_NAME=UPPER(pTABLENAME) AND COLUMN_NAME=UPPER(pCOLUMNNAME);\n" + " IF COUNTER>0 THEN\n" + " dbms_output.put_line(pTABLENAME || ' tablosunda ' || pCOLUMNNAME || ' kolonu var.');\n" + " ELSE\n" + " EXECUTE IMMEDIATE pSQL;\n" + " dbms_output.put_line(pTABLENAME || ' tablosuna' || pCOLUMNNAME || ' kolonu oluÅ?turuldu.');\n" + " END IF;\n" + " \n" + " EXCEPTION\n" + " WHEN OTHERS THEN\n" + " dbms_output.put_line('HATA: ' || pSQL || ' -> SQLERRM: ' || SQLERRM);\n" + "END;\n" + "/\n\n" + "DECLARE\n" + "COUNTER NUMBER(10) := 0;\n" + "pTABLENAME VARCHAR2(100) := 'ALM_AL3';\n" + "pCOLUMNNAME VARCHAR2(100) := 'PAYCURRENCYUNIT';\n" + "pDATATYPE VARCHAR2(100) := 'NVARCHAR2(3) NULL';\n" + "pSQL VARCHAR2(32000) := '\n" + "ALTER TABLE ' || pTABLENAME || ' ADD ' || pCOLUMNNAME || ' ' || pDATATYPE;\n" + "BEGIN\n" + " SELECT COUNT(0) INTO COUNTER FROM USER_TAB_COLUMNS WHERE TABLE_NAME=UPPER(pTABLENAME) AND COLUMN_NAME=UPPER(pCOLUMNNAME);\n" + " IF COUNTER>0 THEN\n" + " dbms_output.put_line(pTABLENAME || ' tablosunda ' || pCOLUMNNAME || ' kolonu var.');\n" + " ELSE\n" + " EXECUTE IMMEDIATE pSQL;\n" + " dbms_output.put_line(pTABLENAME || ' tablosuna' || pCOLUMNNAME || ' kolonu oluÅ?turuldu.');\n" + " END IF;\n" + " \n" + " EXCEPTION\n" + " WHEN OTHERS THEN\n" + " dbms_output.put_line('HATA: ' || pSQL || ' -> SQLERRM: ' || SQLERRM);\n" + "END;\n" + "/"; final Pattern pattern = Pattern.compile(regex, Pattern.CASE_INSENSITIVE | Pattern.UNICODE_CHARACTER_CLASS); final Matcher matcher = pattern.matcher(string); while (matcher.find()) { System.out.println("Full match: " + matcher.group(0)); for (int i = 1; i <= matcher.groupCount(); i++) { System.out.println("Group " + i + ": " + matcher.group(i)); } } } }

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 Java, please visit: https://docs.oracle.com/javase/7/docs/api/java/util/regex/Pattern.html