fabian/zeitlaeufer
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Learn to work when run via jar instead of via .class file directly

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fszimnau
2025-11-19 13:57:28 +01:00
parent 094dfd9daf
commit 664c6108a5
1 changed files with 33 additions and 14 deletions
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47
src/main/java/de/szimnau/zeitlaeufer/Main.java
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@@ -2,13 +2,17 @@ package de.szimnau.zeitlaeufer;
import java.io.BufferedReader; import java.io.BufferedReader;
import java.io.IOException; import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader; import java.io.InputStreamReader;
import java.lang.reflect.InvocationTargetException; import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.net.URL;
import java.net.URLDecoder;
import java.nio.charset.StandardCharsets; import java.nio.charset.StandardCharsets;
import java.util.*; import java.util.*;
import java.util.concurrent.atomic.AtomicInteger; import java.util.concurrent.atomic.AtomicInteger;
import java.util.function.Function; import java.util.function.Function;
import java.util.jar.JarEntry;
import java.util.jar.JarFile;
import java.util.stream.Collectors; import java.util.stream.Collectors;
import static de.szimnau.zeitlaeufer.tools.CommonTools.print; import static de.szimnau.zeitlaeufer.tools.CommonTools.print;
@@ -27,26 +31,41 @@ public class Main {
private static void askParametersAndRun() throws IOException, NoSuchMethodException, InvocationTargetException, IllegalAccessException { private static void askParametersAndRun() throws IOException, NoSuchMethodException, InvocationTargetException, IllegalAccessException {
var br = new BufferedReader(new InputStreamReader(System.in, StandardCharsets.UTF_8)); var br = new BufferedReader(new InputStreamReader(System.in, StandardCharsets.UTF_8));
Map<Integer, Class<?>> classes = getAllrelevantClasses(); SortedMap<Integer, Class<?>> classes = getAllrelevantClasses();
String printedClasses = classes.entrySet().stream() String printedClasses = classes.entrySet().stream()
.map(e -> e.getKey() + ": " + e.getValue().getCanonicalName().substring(e.getValue().getCanonicalName().lastIndexOf('.') + 1)) .map(e -> e.getKey() + ": " + e.getValue().getCanonicalName().substring(e.getValue().getCanonicalName().lastIndexOf('.') + 1))
.reduce("", (a, b) -> a + "\n" + b); .reduce("", (a, b) -> a + "\n" + b);
print("Welcher Zeitläufer soll verwendet werden? " + printedClasses + "\n: "); print("Welcher Zeitläufer soll verwendet werden? " + printedClasses + "\n: ");
var num = Integer.parseInt(br.readLine()); var num = Integer.parseInt(br.readLine());
Class<?> selectedClass = classes.get(num); Class<?> selectedClass = classes.get(num);
var mainMethod = selectedClass.getMethod("main", String[].class); Method mainMethod = selectedClass.getMethod("main", String[].class);
mainMethod.invoke(null, (Object) new String[0]); mainMethod.invoke(null, (Object) new String[0]);
} }
private static Map<Integer, Class<?>> getAllrelevantClasses() { private static SortedMap<Integer, Class<?>> getAllrelevantClasses() {
InputStream stream = ClassLoader.getSystemClassLoader() ClassLoader classLoader = Thread.currentThread().getContextClassLoader();
.getResourceAsStream("de/szimnau/zeitlaeufer"); List<String> fileNames = new ArrayList<>();
var br = new BufferedReader(new InputStreamReader(stream, StandardCharsets.UTF_8)); URL jarUrl = classLoader.getResource("de/szimnau/zeitlaeufer");
String path = jarUrl.getPath().split(":", 2)[1];
String cleanPath = path.substring(0, path.lastIndexOf('!'));
Enumeration<JarEntry> entries;
try (var jarFile = new JarFile(URLDecoder.decode(cleanPath, StandardCharsets.UTF_8))) {
entries = jarFile.entries();
} catch (IOException e) {
throw new RuntimeException(e);
}
while (entries.hasMoreElements()) {
JarEntry entry = entries.nextElement();
if (entry.isDirectory()) {
continue;
}
fileNames.add(entry.getName());
}
var increment = new AtomicInteger(); var increment = new AtomicInteger();
return Collections.unmodifiableSortedMap(new TreeMap<>( return Collections.unmodifiableSortedMap(new TreeMap<>(
br.lines() fileNames.stream()
.filter(line -> line.endsWith(".class") && !"Main.class".equals(line)) .filter(line -> line.endsWith(".class") && !line.endsWith("module-info.class") && !line.endsWith("Main.class"))
.sorted() .sorted()
.map(Main::getClass) .map(Main::getClass)
.filter(Objects::nonNull) .filter(Objects::nonNull)
@@ -61,23 +80,23 @@ public class Main {
private static Class<?> getClass(String className) { private static Class<?> getClass(String className) {
return getClassForName(className.substring(0, className.lastIndexOf('.'))); String classWithPath = className.replace("/", ".");
return getClassForName(classWithPath.substring(0, className.lastIndexOf('.')));
} }
private static Class<?> getClassForName(String className) { private static Class<?> getClassForName(String className) {
String fqnClassName = "de.szimnau.zeitlaeufer." + className;
try { try {
return Class.forName(fqnClassName); return Class.forName(className);
} catch (ClassNotFoundException cnfe) { } catch (ClassNotFoundException cnfe) {
println("ERROR: could not find Class for Name: de.szimnau.zeitlaeufer." + fqnClassName); println("ERROR: could not find Class for Name: de.szimnau.zeitlaeufer." + className);
} }
return null; return null;
} }
private static void parseParametersAndRun(String[] args) throws NoSuchMethodException, InvocationTargetException, IllegalAccessException { private static void parseParametersAndRun(String[] args) throws NoSuchMethodException, InvocationTargetException, IllegalAccessException {
Class<?> selectedClass = getClassForName(args[0]); Class<?> selectedClass = getClassForName("de.szimnau.zeitlaeufer." + args[0]);
if (selectedClass == null) { if (selectedClass == null) {
System.exit(1); System.exit(1);
} }