ClassInfoClassWriter.java

package de.take_weiland.mods.commons.asm;

import de.take_weiland.mods.commons.asm.info.ClassInfo;
import org.objectweb.asm.ClassReader;
import org.objectweb.asm.ClassWriter;

/**
 * <p>A {@code ClassWriter} that does not use {@code Class.forName} to determine the "common superclass" of two types but instead uses
 * {@link de.take_weiland.mods.commons.asm.info.ClassInfo}. This way {@code COMPUTE_FRAMES} can be used reliably even in edge cases where
 * the currently transformed class would have to be loaded has self-references.</p>
 */
public class ClassInfoClassWriter extends ClassWriter {

	public ClassInfoClassWriter(int flags) {
		super(flags);
	}

    public ClassInfoClassWriter(ClassReader classReader, int flags) {
        super(classReader, flags);
    }

    @Override
	protected String getCommonSuperClass(String type1, String type2) {
		ClassInfo cl1 = ClassInfo.of(type1);
		ClassInfo cl2 = ClassInfo.of(type2);

		if (cl1.isAssignableFrom(cl2)) {
			return type1;
		}
		if (cl2.isAssignableFrom(cl1)) {
			return type2;
		}
		if (cl1.isInterface() || cl2.isInterface()) {
			return "java/lang/Object";
		} else {
			do {
				cl1 = ClassInfo.of(cl1.superName());
			} while (!cl1.isAssignableFrom(cl2));
			return cl1.internalName();
		}
	}

}