My HTMLEncode function in Java

Posted by Niklas on September 29, 2015 Leave a comment (0) Go to comments

Every now and then I have to work in an environment where imports of frameworks is prohibited and it in times like that that I had to create my own HTMLEncode function. Here is the result:

public static String HTMLEncode(String inputString) {
 
		// Check if string contains ANY special characters (<>"&)
		if(inputString.indexOf("<") != -1 || 
                   inputString.indexOf(">") != -1 || 
                   inputString.indexOf("\"") != -1 ||
                   inputString.indexOf("&") != -1) {
 
			char c;
			StringBuffer out = new StringBuffer();
			for(int i=0; i < inputString.length(); i++) {
 
			    c = inputString.charAt(i);
 
			    if(c=='"' || c=='<' || c=='>') {
			       out.append("&#"+(int)c+";");
			    }
			    else if(c == '&'){
                                // Is &-sign preceding an HTML entity?
			    	if(inputString.indexOf("&amp;", i) == i || 
			    		inputString.indexOf("& #38;", i) == i ||
		    			inputString.indexOf("& lt;", i)  == i || 
		    			inputString.indexOf("& #60;", i) == i ||
		    			inputString.indexOf("& gt;", i)  == i ||
		    			inputString.indexOf("& #62;", i) == i ||
		    			inputString.indexOf("& quot;", i)== i ||
		    			inputString.indexOf("& #34;", i) == i ){
 
			    		out.append(c);
 
			    	}
			    	else {
			    		out.append("&#"+(int)c+";");
			    	}
			    }
			    else {
			        out.append(c);
			    }		
			}			
			return out.toString();
		}
		else {
			return inputString;			
		}				
	}