Integrate GVK plugin

AUTHORS

@@ -13,6 +13,7 @@ Andreas Amann
 Andreas Rudert
 Behrouz Javanmardi
 Bernd Kalbfuss
+Bernhard Tempel
 Brian Quistorff
 Brian Van Essen
 captain123
@@ -49,6 +50,7 @@ Hannes Restel
 Igor Chernyavsky
 Igor Steinmacher
 Ingvar Jackal
+Jan Frederik Maas
 Jan Kubovy
 Janosch Kutscherauer
 Jason Pickering

CHANGELOG.md

@@ -60,6 +60,7 @@ to [sourceforge feature requests](https://sourceforge.net/p/jabref/features/) by
  - Feature: New LabelPattern `[keywordsN]`, where N is optional. Returns the first N keywords. If no N is specified ("`[keywords]`"), all keywords are returned. Spaces are removed.
  - Update supported LookAndFeels
  - Show replaced journal abbreviations on console
+ - Integrated [GVK-Plugin](http://www.gbv.de/wikis/cls/Jabref-GVK-Plugin)
  - The three options to manage file references are moved to their own separated group in the Tools menu. 
 
 ### Fixed

scripts/generate-authors.sh

@@ -51,6 +51,7 @@ cd "$(dirname "$(readlink -f "$BASH_SOURCE")")/.."
 	John Zedlewski
 	Samin Muhammad Ridwanul Karim
 	Stefan Robert
+	Bernhard Tempel
 	EOF
 
 	# %aN = author name, %aE = author email

src/main/java/net/sf/jabref/bibtex/EntryTypes.java

@@ -74,24 +74,15 @@ private static void initBibtexEntryTypes() {
      * or null if it does not exist.
      */
     public static EntryType getType(String name) {
-        EntryType entryType = ALL_TYPES.get(name.toLowerCase());
-        if (entryType == null) {
-            return null;
-        }
-        return entryType;
+        return ALL_TYPES.get(name.toLowerCase());
     }
 
     /**
      * This method returns the standard BibtexEntryType for the
      * name of a type, or null if it does not exist.
      */
     public static EntryType getStandardType(String name) {
-        EntryType entryType = STANDARD_TYPES.get(name.toLowerCase());
-        if (entryType == null) {
-            return null;
-        } else {
-            return entryType;
-        }
+        return STANDARD_TYPES.get(name.toLowerCase());
     }
 
     public static void addOrModifyCustomEntryType(CustomEntryType type) {

src/main/java/net/sf/jabref/importer/fetcher/EntryFetchers.java

@@ -31,6 +31,7 @@ public EntryFetchers() {
         entryFetchers.add(new DBLPFetcher());
         entryFetchers.add(new DiVAtoBibTeXFetcher());
         entryFetchers.add(new DOItoBibTeXFetcher());
+        entryFetchers.add(new GVKFetcher());
         entryFetchers.add(new IEEEXploreFetcher());
         entryFetchers.add(new INSPIREFetcher());
         entryFetchers.add(new ISBNtoBibTeXFetcher());

src/main/java/net/sf/jabref/importer/fetcher/GVKFetcher.java

@@ -0,0 +1,186 @@
+/**
+ * License: GPLv2, but Jan Frederik Maas agreed to change license upon request
+ */
+package net.sf.jabref.importer.fetcher;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.UnsupportedEncodingException;
+import java.net.URI;
+import java.net.URISyntaxException;
+import java.net.URL;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.List;
+
+import javax.swing.JPanel;
+import javax.xml.parsers.ParserConfigurationException;
+
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+import org.xml.sax.SAXException;
+
+import net.sf.jabref.importer.ImportInspector;
+import net.sf.jabref.importer.OutputPrinter;
+import net.sf.jabref.logic.l10n.Localization;
+import net.sf.jabref.model.entry.BibtexEntry;
+
+import java.net.URLEncoder;
+
+/**
+ * Fetch or search from GVK http://gso.gbv.de/sru/DB=2.1/
+ */
+public class GVKFetcher implements EntryFetcher {
+
+    private static final Log LOGGER = LogFactory.getLog(GVKFetcher.class);
+
+    HashMap<String, String> searchKeys = new HashMap<>();
+
+
+    public GVKFetcher() {
+        searchKeys.put("all", "pica.all%3D");
+        searchKeys.put("tit", "pica.tit%3D");
+        searchKeys.put("per", "pica.per%3D");
+        searchKeys.put("thm", "pica.thm%3D");
+        searchKeys.put("slw", "pica.slw%3D");
+        searchKeys.put("txt", "pica.txt%3D");
+        searchKeys.put("num", "pica.num%3D");
+        searchKeys.put("kon", "pica.kon%3D");
+        searchKeys.put("ppn", "pica.ppn%3D");
+        searchKeys.put("bkl", "pica.bkl%3D");
+        searchKeys.put("erj", "pica.erj%3D");
+    }
+
+    /**
+     * Necessary for JabRef
+     */
+    @Override
+    public void stopFetching() {
+        // not supported
+    }
+
+    @Override
+    public String getHelpPage() {
+        return "GVKHelp.html";
+    }
+
+    @Override
+    public JPanel getOptionsPanel() {
+        return null;
+    }
+
+    @Override
+    public String getTitle() {
+        return "GVK (Gemeinsamer Verbundkatalog)";
+    }
+
+    @Override
+    public boolean processQuery(String query, ImportInspector dialog, OutputPrinter frame) {
+        String gvkQuery = "";
+
+        query = query.trim();
+
+        String[] qterms = query.split("\\s");
+
+        // Null abfangen!
+        if (qterms.length == 0) {
+            return false;
+        }
+
+        // Jeden einzelnen Suchbegriff URL-Encodieren
+        for (int x = 0; x < qterms.length; x++) {
+            try {
+                qterms[x] = URLEncoder.encode(qterms[x], "UTF-8");
+            } catch (UnsupportedEncodingException e) {
+                LOGGER.error("Unsupported encoding", e);
+            }
+        }
+
+        if (searchKeys.containsKey(qterms[0])) {
+            gvkQuery = processComplexQuery(qterms);
+        } else {
+            gvkQuery = "pica.all%3D";
+            gvkQuery = gvkQuery.concat(qterms[0]);
+
+            for (int x = 1; x < qterms.length; x++) {
+                gvkQuery = gvkQuery.concat("%20");
+                gvkQuery = gvkQuery.concat(qterms[x]);
+            }
+        }
+
+        List<BibtexEntry> bibs = fetchGVK(gvkQuery);
+
+        for (BibtexEntry entry : bibs) {
+            dialog.addEntry(entry);
+        }
+
+        if (bibs.size() == 0) {
+            frame.showMessage(Localization.lang("No references found"));
+        }
+
+        return true;
+    }
+
+    private String processComplexQuery(String[] s) {
+        String result = "";
+        boolean lastWasKey = false;
+
+        for (int x = 0; x < s.length; x++) {
+            if (searchKeys.containsKey(s[x])) {
+                if (!(x == 0)) {
+                    result = result.concat("%20and%20" + searchKeys.get(s[x]));
+                } else {
+                    result = searchKeys.get(s[x]);
+                }
+                lastWasKey = true;
+            } else {
+                if (!lastWasKey) {
+                    result = result.concat("%20");
+                }
+                String encoded = s[x];
+                encoded = encoded.replaceAll(",", "%2C");
+                encoded = encoded.replaceAll("\\?", "%3F");
+
+                result = result.concat(encoded);
+                lastWasKey = false;
+            }
+        }
+        return (result);
+    }
+
+    private List<BibtexEntry> fetchGVK(String query) {
+        List<BibtexEntry> result;
+
+        String urlPrefix = "http://sru.gbv.de/gvk?version=1.1&operation=searchRetrieve&query=";
+        String urlQuery = query;
+        String urlSuffix = "&maximumRecords=50&recordSchema=picaxml&sortKeys=Year%2C%2C1";
+
+        String searchstring = (urlPrefix + urlQuery + urlSuffix);
+        LOGGER.debug(searchstring);
+        try {
+            URI uri = null;
+            try {
+                uri = new URI(searchstring);
+            } catch (URISyntaxException e) {
+                LOGGER.error("URI malformed error", e);
+                return Collections.EMPTY_LIST;
+            }
+            URL url = uri.toURL();
+            try (InputStream is = url.openStream()) {
+                result = (new GVKParser()).parseEntries(is);
+            }
+        } catch (IOException e) {
+            LOGGER.error("GVK plugin: An I/O exception occurred", e);
+            return Collections.EMPTY_LIST;
+        } catch (ParserConfigurationException e) {
+            LOGGER.error("GVK plugin: An internal parser error occurred", e);
+            return Collections.EMPTY_LIST;
+        } catch (SAXException e) {
+            LOGGER.error("An internal parser error occurred", e);
+            return Collections.EMPTY_LIST;
+        }
+
+        return result;
+    }
+
+}