waluty - wersje XPath

src/main/java/p20_xml/Waluty2_XPath.java

@@ -38,19 +38,16 @@ public class Waluty2_XPath {
             for(int i = 0; i < n; i++) {
                 Node table = tables.item(i);
                 String effectiveDate = xpath.evaluate("EffectiveDate", table);
-                System.out.println(effectiveDate);
-                NodeList rates = (NodeList) xpath.evaluate("Rates/Rate", table, XPathConstants.NODESET);
+                // System.out.println(effectiveDate);
+                NodeList rates = (NodeList) xpath.evaluate("Rates/Rate[Code='" + waluta + "']", table, XPathConstants.NODESET);
                 final int m = rates.getLength();
                 for(int j = 0; j < m; j++) {
-                    Element rate = (Element) rates.item(j);
-                    String code = xpath.evaluate("Code", rate);
-                    if(code.equals(waluta)) {
-                        double mid = (Double) xpath.evaluate("Mid", rate, XPathConstants.NUMBER);
-                        count++;
-                        sum += mid;
-                        if(mid < min) min = mid;
-                        if(mid > max) max = mid;
-                    }
+                    Node rate = rates.item(j);
+                    double mid = (Double) xpath.evaluate("Mid", rate, XPathConstants.NUMBER);
+                    count++;
+                    sum += mid;
+                    if(mid < min) min = mid;
+                    if(mid > max) max = mid;
                 }
             }
             long t3 = System.nanoTime();

src/main/java/p20_xml/Waluty3_XPath.java

+package p20_xml;
+
+import org.w3c.dom.Document;
+import org.w3c.dom.Node;
+import org.w3c.dom.NodeList;
+import org.xml.sax.InputSource;
+
+import javax.xml.parsers.DocumentBuilder;
+import javax.xml.parsers.DocumentBuilderFactory;
+import javax.xml.xpath.XPath;
+import javax.xml.xpath.XPathConstants;
+import javax.xml.xpath.XPathExpression;
+import javax.xml.xpath.XPathFactory;
+import java.io.File;
+
+public class Waluty3_XPath {
+    // W tej wersji staram się od razu jak najwięcej wyrazić w języku XPath, a jak najmiej pisać w Javie.
+
+    public static void main(String[] args) {
+        String plik = "pliki/waluty2023.xml";
+        String waluta = "EUR";
+
+        System.out.println("Startujemy");
+        long t1 = System.nanoTime();
+        try {
+            XPathFactory xpf = XPathFactory.newInstance();
+            XPath xpath = xpf.newXPath();
+            XPathExpression kropka = xpath.compile(".");
+            InputSource src = new InputSource(plik);
+
+            long t2 = System.nanoTime();
+
+            double min = Double.MAX_VALUE, max = 0, sum = 0;
+
+            waluta = waluta.replace("'", "''"); // eskejpowanie dla bezpieczeństwa
+            final String expr = "/ArrayOfExchangeRatesTable/ExchangeRatesTable/Rates/Rate[Code='" + waluta + "']/Mid";
+            NodeList mids = (NodeList) xpath.evaluate(expr, src, XPathConstants.NODESET);
+            final int count = mids.getLength();
+            for(int i = 0; i < count; i++) {
+                double mid = (Double) kropka.evaluate(mids.item(i), XPathConstants.NUMBER);
+                sum += mid;
+                if(mid < min) min = mid;
+                if(mid > max) max = mid;
+            }
+            long t3 = System.nanoTime();
+            Runtime runtime = Runtime.getRuntime();
+            long pamiec = runtime.totalMemory() - runtime.freeMemory();
+
+            System.out.printf("Czas łączny        : %.6f s%n", (t3-t1) * 1e-9);
+            System.out.printf("Zajęta pamięć      : %,d B%n", pamiec);
+            System.out.println("Count: " + count);
+            if(count > 0) {
+                System.out.println("Sum: " + sum);
+                System.out.println("Avg: " + (sum / count));
+                System.out.println("Min: " + min);
+                System.out.println("Max: " + max);
+            }
+        } catch (Exception e) {
+            e.printStackTrace();
+        }
+    }
+}

src/main/java/p20_xml/Waluty3a_XPath_TylkoSuma.java

+package p20_xml;
+
+import org.w3c.dom.Document;
+import org.w3c.dom.NodeList;
+import org.xml.sax.InputSource;
+
+import javax.xml.parsers.DocumentBuilder;
+import javax.xml.parsers.DocumentBuilderFactory;
+import javax.xml.xpath.XPath;
+import javax.xml.xpath.XPathConstants;
+import javax.xml.xpath.XPathExpression;
+import javax.xml.xpath.XPathFactory;
+import java.io.File;
+import java.io.FileInputStream;
+
+public class Waluty3a_XPath_TylkoSuma {
+    // W tej wersji staram się od razu jak najwięcej wyrazić w języku XPath, a jak najmiej pisać w Javie.
+
+    public static void main(String[] args) {
+        String plik = "pliki/waluty2023.xml";
+        String waluta = "EUR";
+
+        System.out.println("Startujemy");
+        long t1 = System.nanoTime();
+        try {
+            XPathFactory xpf = XPathFactory.newInstance();
+            XPath xpath = xpf.newXPath();
+            InputSource src = new InputSource(plik);
+
+            long t2 = System.nanoTime();
+
+            waluta = waluta.replace("'", "''"); // eskejpowanie dla bezpieczeństwa
+            final String expr = "sum(/ArrayOfExchangeRatesTable/ExchangeRatesTable/Rates/Rate[Code='" + waluta + "']/Mid)";
+            double sum = (Double)xpath.evaluate(expr, src, XPathConstants.NUMBER);
+
+            long t3 = System.nanoTime();
+            Runtime runtime = Runtime.getRuntime();
+            long pamiec = runtime.totalMemory() - runtime.freeMemory();
+
+            System.out.printf("Czas czytania pliku: %.6f s%n", (t2-t1) * 1e-9);
+            System.out.printf("Czas liczenia      : %.6f s%n", (t3-t2) * 1e-9);
+            System.out.printf("Czas łączny        : %.6f s%n", (t3-t1) * 1e-9);
+            System.out.printf("Zajęta pamięć      : %,d B%n", pamiec);
+            System.out.println("Sum: " + sum);
+        } catch (Exception e) {
+            e.printStackTrace();
+        }
+    }
+}