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package test;
import org.biojava.utils.bytecode.*;
import java.util.*;
import java.io.*;
public class MakeHelloWorld {
public static void main(String[] args) throws Exception {
CodeClass cl_Object = IntrospectedCodeClass.forClass("java.lang.Object");
CodeClass cl_String = IntrospectedCodeClass.forClass("java.lang.String");
CodeClass cl_System = IntrospectedCodeClass.forClass("java.lang.System");
CodeClass cl_PrintStream = IntrospectedCodeClass.forClass("java.io.PrintStream");
CodeClass cl_pVoid = IntrospectedCodeClass.forClass(Void.TYPE);
CodeClass i_Runnable = IntrospectedCodeClass.forClass(Runnable.class);
CodeClass[] aInterfaces = { i_Runnable };
CodeField f_System_out = cl_System.getFieldByName("out");
CodeMethod m_PrintStream_println_I = oneIntMethod(cl_PrintStream.getMethodsByName("println"));
CodeMethod m_Object_init = new SimpleCodeMethod("<init>", cl_Object, cl_pVoid,
new ArrayList(), CodeUtils.ACC_PUBLIC);
CodeClass[] aMethodArgs = {};
GeneratedCodeClass cc = new GeneratedCodeClass("MyTestClass",
IntrospectedCodeClass.forClass("java.lang.Object"),
aInterfaces,
CodeUtils.ACC_PUBLIC | CodeUtils.ACC_SUPER);
GeneratedCodeMethod init = cc.createMethod("<init>",
cl_pVoid,
aMethodArgs,
CodeUtils.ACC_PUBLIC);
InstructionVector iv = new InstructionVector();
iv.add(ByteCode.make_aload(init.getThis()));
iv.add(ByteCode.make_invokespecial(m_Object_init));
iv.add(ByteCode.make_return());
cc.setCodeGenerator(init, iv);
GeneratedCodeMethod run = cc.createMethod("run",
cl_pVoid,
aMethodArgs,
CodeUtils.ACC_PUBLIC);
iv = new InstructionVector();
Label loopTest = new Label();
Label loopStart = new Label();
Label loopEnd = new Label();
iv.add(ByteCode.make_iconst(1));
iv.add(ByteCode.make_goto(loopStart));
iv.add(loopTest);
iv.add(ByteCode.make_dup());
iv.add(ByteCode.make_iconst(10));
iv.add(ByteCode.make_if_icmpgt(loopEnd));
iv.add(loopStart);
iv.add(ByteCode.make_dup());
iv.add(ByteCode.make_getstatic(f_System_out));
iv.add(ByteCode.make_swap());
iv.add(ByteCode.make_invokevirtual(m_PrintStream_println_I));
iv.add(ByteCode.make_iconst(1));
iv.add(ByteCode.make_iadd());
iv.add(ByteCode.make_goto(loopTest));
iv.add(loopEnd);
iv.add(ByteCode.make_return());
cc.setCodeGenerator(run, iv);
FileOutputStream fos = new FileOutputStream("MyTestClass.class");
cc.createCode(fos);
fos.close();
}
static CodeMethod oneIntMethod(Set methods) {
CodeClass cl_pInt = IntrospectedCodeClass.forClass(Integer.TYPE);
for (Iterator i = methods.iterator(); i.hasNext(); ) {
CodeMethod cm = (CodeMethod) i.next();
if (cm.numParameters() != 1)
continue;
if (cm.getParameterType(0) == cl_pInt)
return cm;
}
return null;
}
}
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