控制行号时的字节码库是什么？
我需要从现有类生成新类（通过生成java字节代码）。我将分析类的方法的主体（表达式）。表达式将决定我将生成什么代码。
对我来说，它是import和设置新类的源文件（与基本java文件相同）以及控制行号（当抛出异常时，stacktrace应该包含基本java文件的行号）。
例：
我有文件BaseClass.java。编译器从中生成BaseClass.class。我想分析这个类文件并生成GeneratedClass.class的字节代码。当在c处抛出异常时，stacktrace应包含“BaseClass.java第3行”。
BaseClass.java
1: class BaseClass {
2: void method() {
3: call();
4: }
5:}
GeneratesClaas.class
a: class GeneratedClass {
b: void generatedMethod() {
c: generatedCall();
d: }
e:}
没有找到相关结果
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import java.io.File; import org.objectweb.asm.Label; import org.objectweb.asm.MethodVisitor; import java.io.FileOutputStream; import java.io.IOException; import org.objectweb.asm.ClassWriter; import org.objectweb.asm.util.CheckClassAdapter; import static org.objectweb.asm.Opcodes.*; public class App { public static void main(String[] args) throws IOException { ClassWriter cw = new ClassWriter(0); CheckClassAdapter ca = new CheckClassAdapter(cw); ca.visit(V1_5, ACC_PUBLIC + ACC_SUPER, "test/Test", null, "java/lang/Object", null); ca.visitSource("this/file/does/not/exist.txt", null); // Not sure what the second parameter does MethodVisitor mv = ca.visitMethod(ACC_PUBLIC | ACC_STATIC, "main", "([Ljava/lang/String;)V", null, null); mv.visitCode(); Label label = new Label(); mv.visitLabel(label); mv.visitLineNumber(123, label); mv.visitTypeInsn(NEW, "java/lang/RuntimeException"); mv.visitInsn(DUP); mv.visitMethodInsn(INVOKESPECIAL, "java/lang/RuntimeException", "<init>", "()V"); mv.visitInsn(ATHROW); mv.visitInsn(RETURN); mv.visitMaxs(2, 1); mv.visitEnd(); ca.visitEnd(); File target = new File("target/classes/test/"); target.mkdirs(); FileOutputStream out = new FileOutputStream(new File(target, "Test.class")); out.write(cw.toByteArray()); out.close(); } }$ javap -classpath target/classes/ -c -l test.Test Compiled from "this.file.does.not.exist.txt" public class test.Test extends java.lang.Object{ public static void main(java.lang.String[]); Code: 0: new #9; //class java/lang/RuntimeException 3: dup 4: invokespecial #13; //Method java/lang/RuntimeException."<init>":()V 7: athrow 8: return LineNumberTable: line 123: 0 }$ java -cp target/classes/ test.Test Exception in thread "main" java.lang.RuntimeException at test.Test.main(this/file/does/not/exist.txt:123)艰管垮淮