HTML tag Regular Expression Pattern
<("[^"]*"|'[^']*'|[^'">])*>
Description
<#start with opening tag"<"
(# start of group #1
"[^"]*" # allow string with double quotes enclosed - "string"
|#..or
'[^']*' # allow string with single quote enclosed - 'string'
|#..or
[^'">] # cant contains one single quotes, double quotes and ">"
)# end of group #1
*#0or more
> #end with closing tag ">"
Code:
package com.codewr.javacore.regular.expression;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
/**
*
* @author codewr
*/
public class HTMLTagValidator {
private static final String HTML_TAG_PATTERN = "<(\"[^\"]*\"|'[^']*'|[^'\">])*>";
public static void main(String[] args) {
HTMLTagValidator hTMLTagValidator = new HTMLTagValidator();
//check html tag validate
boolean isValid = hTMLTagValidator.validate("<b>");
System.out.println("email valid is " + isValid);
}
/**
* Validate html tag with regular expression
*
* @param tag html tag for validation
* @return true valid html tag, false invalid html tag
*/
public boolean validate(final String tag) {
Pattern pattern = Pattern.compile(HTML_TAG_PATTERN );
Matcher matcher = pattern.matcher(tag);
return matcher.matches();
}
}
Code UnitTest:
Html tag valid:
1. “<b>” , “<input value=’>’>”
2. “<input value='<‘>” , “<b/>”
3. “<a href=’http://www.google.com’>”
4. “<br>” , “<br/>”
5. “<input value=\”\” id=’test’>” , “<input value=” id=’test’>”
Html tag invalid:
1. “<input value=\” id=’test’>” – one double quotes string is not allow
2. “<input value=’ id=’test’>” – one single quotes string is not allow
3. “<input value=>>” – single opening tag > is not allow , have to enclose with single or double quotes
import com.codewr.javacore.regular.expression.HTMLTagValidator;
import org.testng.Assert;
import org.testng.annotations.*;
/**
* HTMLTag validator Testing
* @author codewr
*
*/
public class HTMLTagValidatorTest {
private HTMLTagValidator htmlTagValidator;
@BeforeClass
public void initData(){
htmlTagValidator = new HTMLTagValidator();
}
@DataProvider
public Object[][] ValidHTMLTagProvider() {
return new Object[][]{
new Object[] {"<b>"},
new Object[] {"<input value='>'>"},
new Object[] {"<input value='<'>"},
new Object[] {"<b/>"},
new Object[] {"<a href='http://www.google.com'>"},
new Object[] {"<br>"},
new Object[] {"<br/>"},
new Object[] {"<input value=\"\" id='test'>"},
new Object[] {"<input value='' id='test'>"}
};
}
@DataProvider
public Object[][] InvalidHTMLTagProvider() {
return new Object[][]{
new Object[] {"<input value=\" id='test'>"},
new Object[] {"<input value=' id='test'>"},
new Object[] {"<input value=>>"}
};
}
@Test(dataProvider = "ValidHTMLTagProvider")
public void ValidHTMLTagTest(String tag) {
boolean valid = htmlTagValidator.validate(tag);
System.out.println("HTMLTag is valid : " + tag + " , " + valid);
Assert.assertEquals(true, valid);
}
@Test(dataProvider = "InvalidHTMLTagProvider",
dependsOnMethods="ValidHTMLTagTest")
public void InValidHTMLTagTest(String tag) {
boolean valid = htmlTagValidator.validate(tag);
System.out.println("HTMLTag is valid : " + tag + " , " + valid);
Assert.assertEquals(false, valid);
}
}
Output:
Running HTMLTagValidatorTest
HTMLTag is valid : <b> , true
HTMLTag is valid : <input value='>'> , true
HTMLTag is valid : <input value='<'> , true
HTMLTag is valid : <b/> , true
HTMLTag is valid : <a href='http://www.google.com'> , true
HTMLTag is valid : <br> , true
HTMLTag is valid : <br/> , true
HTMLTag is valid : <input value="" id='test'> , true
HTMLTag is valid : <input value='' id='test'> , true
HTMLTag is valid : <input value=" id='test'> , false
HTMLTag is valid : <input value=' id='test'> , false
HTMLTag is valid : <input value=>> , false
Tests run: 12, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 0.527 sec
Results :
Tests run: 12, Failures: 0, Errors: 0, Skipped: 0
Note: file pom.xml add maven
<dependency>
<groupId>org.testng</groupId>
<artifactId>testng</artifactId>
<version>6.8</version>
<scope>test</scope>
</dependency>