From 40ffa5591716b6ff16dfcdea7693415af08a71ec Mon Sep 17 00:00:00 2001
From: "Dr. Martin Goik" <goik@hdm-stuttgart.de>
Date: Sat, 23 Feb 2019 19:49:38 +0100
Subject: [PATCH] Cosmetics, Auto close connection
---
.../Solve/src/main/java/Driver.java | 10 +-
.../de/hdm_stuttgart/mi/sda1/Book2Rdbms.java | 149 ++++++++----------
2 files changed, 75 insertions(+), 84 deletions(-)
diff --git a/Klausuren/Sda1/2018Winter/Solve/src/main/java/Driver.java b/Klausuren/Sda1/2018Winter/Solve/src/main/java/Driver.java
index 5aed9b810..ed7f34ded 100644
--- a/Klausuren/Sda1/2018Winter/Solve/src/main/java/Driver.java
+++ b/Klausuren/Sda1/2018Winter/Solve/src/main/java/Driver.java
@@ -2,10 +2,10 @@ import de.hdm_stuttgart.mi.sda1.Book2Rdbms;
public class Driver {
- public static void main(String[] args) {
-
- final Book2Rdbms book2rdbms = new Book2Rdbms();
- book2rdbms.execute();
+ public static void main(String[] args) {
+ try (final Book2Rdbms book2rdbms = new Book2Rdbms()) {
+ book2rdbms.execute();
}
-}
+ }
+}
\ No newline at end of file
diff --git a/Klausuren/Sda1/2018Winter/Solve/src/main/java/de/hdm_stuttgart/mi/sda1/Book2Rdbms.java b/Klausuren/Sda1/2018Winter/Solve/src/main/java/de/hdm_stuttgart/mi/sda1/Book2Rdbms.java
index e547bc658..7705bde1b 100644
--- a/Klausuren/Sda1/2018Winter/Solve/src/main/java/de/hdm_stuttgart/mi/sda1/Book2Rdbms.java
+++ b/Klausuren/Sda1/2018Winter/Solve/src/main/java/de/hdm_stuttgart/mi/sda1/Book2Rdbms.java
@@ -1,10 +1,7 @@
package de.hdm_stuttgart.mi.sda1;
import org.jdom2.*;
-import org.jdom2.filter.ElementFilter;
import org.jdom2.input.SAXBuilder;
-import org.jdom2.xpath.XPathExpression;
-import org.jdom2.xpath.XPathFactory;
import java.io.File;
import java.io.IOException;
@@ -13,91 +10,85 @@ import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.SQLException;
-public class Book2Rdbms implements AutoCloseable{
+public class Book2Rdbms implements AutoCloseable {
- private Connection conn;
+ private Connection conn;
- private PreparedStatement insertSection, insertPara;
+ private PreparedStatement insertSection, insertPara;
- private Document doc;
+ private Element book;
- public Book2Rdbms() {
- try {
- conn = DriverManager.getConnection(
- "jdbc:mysql://localhost/hdm?serverTimezone=UTC", "hdmuser", "XYZ");
- insertSection = conn.prepareStatement(
- "INSERT INTO Section (id, title, parent, revisionFlag) VALUES (?, ?, ?, ?);");
+ public Book2Rdbms() {
+ try {
+ conn = DriverManager.getConnection(
+ "jdbc:mysql://localhost/hdm?serverTimezone=UTC", "hdmuser", "XYZ");
+ insertSection = conn.prepareStatement(
+ "INSERT INTO Section (id, title, parent, revisionFlag) VALUES (?, ?, ?, ?);");
- insertPara = conn.prepareStatement(
- "INSERT INTO Para (section, para, revisionFlag) VALUES (?, ?, ?)");
+ insertPara = conn.prepareStatement(
+ "INSERT INTO Para (section, para, revisionFlag) VALUES (?, ?, ?)");
- } catch (SQLException e) {
- System.err.println("Unable to establish connection: " + e);
- System.exit(1);
- }
-
- final SAXBuilder builder = new SAXBuilder();
- try {
- doc = builder.build(new File("Schema/sampledata.xml"));
- //getClass().getClassLoader().getResource("Schema/sampledata.xml"));
- } catch (JDOMException e) {
- e.printStackTrace();
- System.err.println("Unable to parse input: " + e);
- System.exit(1);
- } catch (IOException e) {
- e.printStackTrace();
- System.err.println("Unable to read input: " + e);
- System.exit(1);
- }
+ } catch (SQLException e) {
+ System.err.println("Unable to establish connection: " + e);
+ System.exit(1);
}
- public void execute() {
-
- final XPathExpression<Element> xpathSearchPara =
- XPathFactory.instance().compile(
- "/book/section" ,
- new ElementFilter(),
- null ,
- Namespace.getNamespace(null));
-
- xpathSearchPara.evaluate(doc).forEach(this::handleSection);
- }
- private void handleSection(final Element section) { // Top level sections
- handleSection(null, section); // No parent.
+ final SAXBuilder builder = new SAXBuilder();
+ try {
+ book = builder.build(new File("Schema/sampledata.xml")).getRootElement();
+ } catch (JDOMException e) {
+ e.printStackTrace();
+ System.err.println("Unable to parse input: " + e);
+ System.exit(1);
+ } catch (IOException e) {
+ e.printStackTrace();
+ System.err.println("Unable to read input: " + e);
+ System.exit(1);
}
-
- private void handleSection(final String parentId, final Element section) {
- try {
- insertSection.setString(1, section.getAttributeValue("id"));
- insertSection.setString(2, section.getChildText("title"));
- insertSection.setString(3, parentId);
- insertSection.setString(4, section.getAttributeValue("revisionflag"));
- insertSection.execute();
-
- section.getChildren("section").forEach( // recurse to child <section> elements
- s -> handleSection(section.getAttributeValue("id") ,s));
-
- section.getChildren("para").forEach( p -> {
- try {
- insertPara.setString(1, section.getAttributeValue("id"));
- insertPara.setString(2, p.getValue());
- insertPara.setString(3, p.getAttributeValue("revisionflag"));
- insertPara.execute();
- } catch (final SQLException e) {
- System.err.println("Unable to insert <para>: " + e);
- System.exit(1);
- }
- }
- );
- } catch (final SQLException e) {
- e.printStackTrace();
- System.err.println("Unable to insert <section>: " + e);
- System.exit(1);
- }
+ }
+
+ public void execute() {
+ // Top level <section> elements do not have a parent --> null.
+ book.getChildren("section").forEach(s -> handleSection(null, s));
+ }
+
+ private void handleSection(final String parentId, final Element section) {
+ try {
+ final String currentSectionId = section.getAttributeValue("id");
+ insertSection.setString(1, currentSectionId);
+ insertSection.setString(2, section.getChildText("title"));
+ insertSection.setString(3, parentId);
+ insertSection.setString(4, section.getAttributeValue("revisionflag"));
+
+ insertSection.execute();
+
+ section.getChildren("para").forEach(p -> {
+ try {
+ insertPara.setString(1, currentSectionId);
+ insertPara.setString(2, p.getValue());
+ insertPara.setString(3, p.getAttributeValue("revisionflag"));
+ insertPara.execute();
+ } catch (final SQLException e) {
+ System.err.println("Unable to insert <para>: " + e);
+ System.exit(1);
+ }
+ }
+ );
+ // recurse to <section> children
+ section.getChildren("section").forEach(s -> handleSection(currentSectionId, s));
+ } catch (final SQLException e) {
+ e.printStackTrace();
+ System.err.println("Unable to insert <section>: " + e);
+ System.exit(1);
}
-
- @Override
- public void close() throws Exception {
- conn.close();
+ }
+
+ @Override
+ public void close(){
+ try {
+ conn.close();
+ } catch (final SQLException e) {
+ e.printStackTrace();
}
+ }
}
\ No newline at end of file
--
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