1. import java.io.File;
  2. import java.net.URL;
  3. import java.util.Properties;
  5. public class DebugResourceLoader {
  7. public static void main(String[] args) {
  8. // Define the base class for the class to be debugged.
  9. DebugClass debugClass = new DebugClass();
  11. // Override the resource loading behavior.
  12. ClassLoader originalClassLoader = ClassLoader.getSystemClassLoader();
  13. ClassLoader debugClassLoader = new DebugClassLoader(originalClassLoader);
  15. // Set the debug class loader.
  16. Thread.currentThread().setClassLoader(debugClassLoader);
  18. try {
  19. // Load the debug class.
  20. debugClass.load();
  22. // Call a method that uses the overridden resources.
  23. debugClass.doSomething();
  25. } catch (Exception e) {
  26. e.printStackTrace();
  27. } finally {
  28. // Restore the original class loader.
  29. Thread.currentThread().setClassLoader(originalClassLoader);
  30. }
  31. }
  33. static class DebugClassLoader extends ClassLoader {
  35. private final ClassLoader parent;
  37. public DebugClassLoader(ClassLoader parent) {
  38. super(parent);
  39. }
  41. @Override
  42. public Class<?> loadClass(String name, ClassLoader parent) throws ClassNotFoundException {
  43. try {
  44. // Attempt to load the class from the original class loader first.
  45. return super.loadClass(name, parent);
  46. } catch (ClassNotFoundException e) {
  47. // If not found, attempt to load from the overrides directory.
  48. File overridesDir = new File("overrides");
  49. if (!overridesDir.exists()) {
  50. overridesDir.mkdirs();
  51. }
  53. File resourceFile = new File(overridesDir, name.replace(".", "/") + ".class");
  54. if (resourceFile.exists()) {
  55. System.out.println("Loading class from override: " + resourceFile.getAbsolutePath());
  56. return Class.forName(name);
  57. } else {
  58. // If still not found, fall back to the original class loader.
  59. System.out.println("Loading class from original class loader: " + name);
  60. return super.loadClass(name, parent);
  61. }
  62. }
  63. }
  64. }
  66. static class DebugClass {
  68. public void load() {
  69. System.out.println("Loading resources...");
  70. }
  72. public void doSomething() {
  73. System.out.println("Doing something with overridden resources.");
  74. // Access resources using the override mechanism.
  75. String resource = getResource("custom_resource.txt");
  76. System.out.println("Resource value: " + resource);
  77. }
  79. //Example resource loading
  80. public String getResource(String resourceName) {
  81. File overridesDir = new File("overrides");
  82. if (!overridesDir.exists()) {
  83. overridesDir.mkdirs();
  84. }
  86. File resourceFile = new File(overridesDir, resourceName);
  88. if (resourceFile.exists()) {
  89. try {
  90. return new String(resourceFile.readAllBytes());
  91. } catch (Exception e) {
  92. return "Error reading resource";
  93. }
  94. } else {
  95. return "Default resource value";
  96. }
  97. }
  98. }
  99. }

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