nd4j-common/src/main/java/org/nd4j/util/StringUtils.java
public static String escapeHTML(String string) {
        if(string == null) {
            return null;
        }
        StringBuilder sb = new StringBuilder();
        boolean lastCharacterWasSpace = false;
        char[] chars = string.toCharArray();
        for(char c : chars) {
            if(c == ' ') {
                if(lastCharacterWasSpace){
                    lastCharacterWasSpace = false;
                    sb.append("&nbsp;");
                }else {
                    lastCharacterWasSpace=true;
                    sb.append(" ");
                }
            }else {
                lastCharacterWasSpace = false;
                switch(c) {
                    case '<': sb.append("&lt;"); break;
                    case '>': sb.append("&gt;"); break;
                    case '&': sb.append("&amp;"); break;
                    case '"': sb.append("&quot;"); break;
                    default : sb.append(c);break;
                }
            }
        }

        return sb.toString();
    }
public static String escapeHTML(String string) {
        if(string == null) {
            return null;
        }
        StringBuilder sb = new StringBuilder();
        boolean lastCharacterWasSpace = false;
        char[] chars = string.toCharArray();
        for(char c : chars) {
            if(c == ' ') {
                if(lastCharacterWasSpace){
                    lastCharacterWasSpace = false;
                    sb.append("&nbsp;");
                }else {
                    lastCharacterWasSpace=true;
                    sb.append(" ");
                }
            }else {
                lastCharacterWasSpace = false;
                switch(c) {
                    case '<': sb.append("&lt;"); break;
                    case '>': sb.append("&gt;"); break;
                    case '&': sb.append("&amp;"); break;
                    case '"': sb.append("&quot;"); break;
                    default : sb.append(c);break;
                }
            }
        }

        return sb.toString();
    }
Escapes HTML Special characters present in the string.
@param string
@return HTML Escaped String representation