Main.java Source code

Introduction

Here is the source code for Main.java

Source

//package com.java2s;
import java.io.File;
import java.io.IOException;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerConfigurationException;
import javax.xml.transform.TransformerException;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;

import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.xml.sax.SAXException;

public class Main {
    public static void addStoreOperation(String file_path, String key, String value) {
        addEntry(file_path, "STORE", key, value);
    }

    private static void addEntry(String file_path, String operation, String key, String value) {

        Document doc = getDocument(file_path);
        if (doc == null) {
            return;
        }

        Element entry_elem = doc.createElement("Entry");
        entry_elem.setAttribute("Type", operation);
        entry_elem.setAttribute("Key", key);
        if (operation.equals("STORE")) {
            entry_elem.appendChild(doc.createTextNode(value));
        }

        Element log_element = (Element) doc.getElementsByTagName("Log").item(0);
        log_element.appendChild(entry_elem);

        saveFile(file_path, doc);

    }

    public static Document getDocument(String file_path) {
        try {
            DocumentBuilderFactory domFactory = DocumentBuilderFactory.newInstance();
            domFactory.setIgnoringComments(true);
            DocumentBuilder builder;
            builder = domFactory.newDocumentBuilder();
            Document doc = builder.parse(new File(file_path));

            return doc;

        } catch (ParserConfigurationException e) {
            e.printStackTrace();
        } catch (SAXException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }

        return null;
    }

    private static void saveFile(String file_path, Document doc) {
        try {
            // write the content into xml file
            TransformerFactory transformerFactory = TransformerFactory.newInstance();
            Transformer transformer;
            transformer = transformerFactory.newTransformer();
            DOMSource source = new DOMSource(doc);
            StreamResult result = new StreamResult(new File(file_path));

            // Output to console for testing
            //StreamResult result = new StreamResult(System.out);

            transformer.transform(source, result);
        } catch (TransformerConfigurationException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (TransformerException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

    }
}