JAVA: Convert String to InputStream

You can use ByteArrayInputStream to convert String to InputStream.
ByteArrayInputStream extends InputStream.

Example:

String content = "Convert string to inputstream";
ByteArrayInputStream stream = new ByteArrayInputStream(content.getBytes());

Reference:
1. http://forums.sun.com/thread.jspa?threadID=670188

2. http://java.sun.com/j2se/1.4.2/docs/api/java/io/ByteArrayInputStream.html

JSTL: Find length of a collection

To get a length of a collection:
${fn:length(tvPackageGroup.addonOptions)}

Include <%@ taglib prefix="fn" uri="http://java.sun.com/jsp/jstl/functions" %> namespace.
http://stackoverflow.com/questions/851880/check-a-collection-size-with-jstl

Sorting a collection in JSTL

javadoc: http://java.sun.com/products/jsp/jstl/1.1/docs/tlddocs/fn/tld-summary.html

JAVA: reverse string interview question

When you go for an interview, lot of companies ask String manipulation questions.

Some of the most common questions are:

• Reverse words in a string (words are separated by spaces) - Most Common
• Reverse String
• Revers the order of words

I have written a code that performs all these functions. Hope this will help you.

/**
 * Created by IntelliJ IDEA.
 * User: priyank
 * Date: Feb 2, 2010
 */
public class StringTest {

    public static void main(String[] args) {
        String str = "My name is khan";
//        String result = reverseString(str);
//        String result = reverseWords(str);
//        String result = reverseSequence(str);
        String result = iReverseSequence(str);

        System.out.println(result);
    }

    static String reverseString(String str) {
        char[] ch = str.toCharArray();
        StringBuilder sb = new StringBuilder();
        for (int i=(ch.length-1);i>=0;i--) {
            sb.append(ch[i]);
        }
        return sb.toString();
    }

    static String reverseWords(String str) {
        String[] st = str.split("\\s");
        StringBuilder sb = new StringBuilder();
        for(int i=0; i < st.length;i++) {
            sb.append(reverseString(st[i])+" ");
        }
        return sb.toString();
    }

    static String reverseSequence(String str) {
        String[] st = str.split("\\s");
        StringBuilder sb = new StringBuilder();
        for(int i=(st.length-1);i>=0;i--) {
            sb.append(st[i]+" ");
        }
        return sb.toString();
    }


    // Without using inbuilt java functions (for ex without using split())
    // I still used substr() though
    static String iReverseSequence(String str) {
        String word = "";
        int lastIndex = str.length();
        for(int i=(str.length()-1);i>=0;i--) {
            if(str.charAt(i) == ' ') {
                word += str.substring(i+1,lastIndex)+" ";
                lastIndex = i;
            }
        }
        word += str.substring(0,lastIndex);
        return word;
    }
}