package org.xukai.jvm.method; import org.xukai.jvm.attr.AttributeInfo; import org.xukai.jvm.attr.CodeAttr; import org.xukai.jvm.clz.ClassFile; import org.xukai.jvm.cmd.ByteCodeCommand; import org.xukai.jvm.constant.UTF8Info; import org.xukai.jvm.loader.ByteCodeIterator; import java.util.ArrayList; import java.util.List; public class Method { private int accessFlag; private int nameIndex; private int descriptorIndex; private CodeAttr codeAttr; private ClassFile clzFile; public ClassFile getClzFile() { return clzFile; } public int getNameIndex() { return nameIndex; } public int getDescriptorIndex() { return descriptorIndex; } public CodeAttr getCodeAttr() { return codeAttr; } public void setCodeAttr(CodeAttr code) { this.codeAttr = code; } public Method(ClassFile clzFile,int accessFlag, int nameIndex, int descriptorIndex) { this.clzFile = clzFile; this.accessFlag = accessFlag; this.nameIndex = nameIndex; this.descriptorIndex = descriptorIndex; } public String toString(){ return getMethodName() +":"+ getMethodDescription(); } public String getMethodName(){ return ((UTF8Info)clzFile.getConstantPool().getConstantInfo(this.nameIndex)).getValue(); } public String getMethodDescription(){ return ((UTF8Info)clzFile.getConstantPool().getConstantInfo(this.descriptorIndex)).getValue(); } public ByteCodeCommand[] getCmds() { return this.getCodeAttr().getCmds(); } public static Method parse(ClassFile clzFile, ByteCodeIterator iter){ int flages = iter.nextToInt(2); int nameIndex = iter.nextToInt(2); int descriptorIndex = iter.nextToInt(2); Method method = new Method(clzFile, flages, nameIndex, descriptorIndex); int attributeCount = iter.nextToInt(2); if (attributeCount > 0) { for (int i = 0; i < attributeCount; i++) { AttributeInfo info = AttributeInfo.parseAttribute(iter, clzFile); if (info instanceof CodeAttr) { method.setCodeAttr((CodeAttr) info); } } } clzFile.addMethod(method); return method; } public List<String> getParameterList(){ // e.g. (Ljava/util/List;Ljava/lang/String;II)V String paramAndType = getMethodDescription(); int first = paramAndType.indexOf("("); int last = paramAndType.lastIndexOf(")"); // e.g. Ljava/util/List;Ljava/lang/String;II String param = paramAndType.substring(first+1, last); List<String> paramList = new ArrayList<String>(); if((null == param) || "".equals(param)){ return paramList; } while(!param.equals("")){ int pos = 0; // 这是一个对象类型 if(param.charAt(pos) == 'L'){ int end = param.indexOf(";"); if(end == -1){ throw new RuntimeException("can't find the ; for a object type"); } paramList.add(param.substring(pos+1,end)); pos = end + 1; } else if(param.charAt(pos) == 'I'){ // int paramList.add("I"); pos ++; } else if(param.charAt(pos) == 'F'){ // float paramList.add("F"); pos ++; } else{ throw new RuntimeException("the param has unsupported type:" + param); } param = param.substring(pos); } return paramList; } }