package com.github.orajavac.coding2017.jvm.test;
import java.util.List;
import org.junit.After;
import org.junit.Assert;
import org.junit.Before;
import org.junit.Test;
import com.github.orajavac.coding2017.jvm.clz.ClassFile;
import com.github.orajavac.coding2017.jvm.clz.ClassIndex;
import com.github.orajavac.coding2017.jvm.constant.ClassInfo;
import com.github.orajavac.coding2017.jvm.constant.ConstantPool;
import com.github.orajavac.coding2017.jvm.constant.MethodRefInfo;
import com.github.orajavac.coding2017.jvm.constant.NameAndTypeInfo;
import com.github.orajavac.coding2017.jvm.constant.UTF8Info;
import com.github.orajavac.coding2017.jvm.field.Field;
import com.github.orajavac.coding2017.jvm.loader.ClassFileLoader;
import com.github.orajavac.coding2017.jvm.method.Method;
public class ClassFileloaderTest {
private static final Object FULL_QUALIFIED_CLASS_NAME = null;
static String path1 = "bin";
static String path2 = "com.github.orajavac.coding2017.jvm.test.EmployeeV1";
static ClassFile clzFile = null;
static {
ClassFileLoader loader = new ClassFileLoader();
loader.addClassPath(path1);
String className = "com.github.orajavac.coding2017.jvm.test.EmployeeV1";
clzFile = loader.loadClass(className);
clzFile.print();
}
@Before
public void setUp() throws Exception {
}
@After
public void tearDown() throws Exception {
}
@Test
public void testClassPath(){
ClassFileLoader loader = new ClassFileLoader();
loader.addClassPath(path1);
loader.addClassPath(path2);
String clzPath = loader.getClassPath();
Assert.assertEquals(path1+";"+path2,clzPath);
}
@Test
public void testClassFileLength() {
ClassFileLoader loader = new ClassFileLoader();
loader.addClassPath(path1);
String className = "com.github.orajavac.coding2017.jvm.test.EmployeeV1";
byte[] byteCodes = loader.readBinaryCode(className);
// 注意:这个字节数可能和你的JVM版本有关系, 你可以看看编译好的类到底有多大
Assert.assertEquals(1088, byteCodes.length);
}
@Test
public void testMagicNumber(){
ClassFileLoader loader = new ClassFileLoader();
loader.addClassPath(path1);
String className = "com.github.orajavac.coding2017.jvm.test.EmployeeV1";
byte[] byteCodes = loader.readBinaryCode(className);
byte[] codes = new byte[]{byteCodes[0],byteCodes[1],byteCodes[2],byteCodes[3]};
String acctualValue = this.byteToHexString(codes);
Assert.assertEquals("cafebabe", acctualValue);
}
@Test
public void testVersion(){
Assert.assertEquals(0, clzFile.getMinorVersion());
Assert.assertEquals(51, clzFile.getMajorVersion());
}
@Test
public void testConstantPool(){
ConstantPool pool = clzFile.getConstantPool();
Assert.assertEquals(53, pool.getSize());
{
ClassInfo clzInfo = (ClassInfo) pool.getConstantInfo(1);
Assert.assertEquals(2, clzInfo.getUtf8Index());
UTF8Info utf8Info = (UTF8Info) pool.getConstantInfo(2);
Assert.assertEquals(FULL_QUALIFIED_CLASS_NAME, utf8Info.getValue());
}
{
ClassInfo clzInfo = (ClassInfo) pool.getConstantInfo(3);
Assert.assertEquals(4, clzInfo.getUtf8Index());
UTF8Info utf8Info = (UTF8Info) pool.getConstantInfo(4);
Assert.assertEquals("java/lang/Object", utf8Info.getValue());
}
{
UTF8Info utf8Info = (UTF8Info) pool.getConstantInfo(5);
Assert.assertEquals("name", utf8Info.getValue());
utf8Info = (UTF8Info) pool.getConstantInfo(6);
Assert.assertEquals("Ljava/lang/String;", utf8Info.getValue());
utf8Info = (UTF8Info) pool.getConstantInfo(7);
Assert.assertEquals("age", utf8Info.getValue());
utf8Info = (UTF8Info) pool.getConstantInfo(8);
Assert.assertEquals("I", utf8Info.getValue());
utf8Info = (UTF8Info) pool.getConstantInfo(9);
Assert.assertEquals("<init>", utf8Info.getValue());
utf8Info = (UTF8Info) pool.getConstantInfo(10);
Assert.assertEquals("(Ljava/lang/String;I)V", utf8Info.getValue());
utf8Info = (UTF8Info) pool.getConstantInfo(11);
Assert.assertEquals("Code", utf8Info.getValue());
}
{
MethodRefInfo methodRef = (MethodRefInfo)pool.getConstantInfo(12);
Assert.assertEquals(3, methodRef.getClassInfoIndex());
Assert.assertEquals(13, methodRef.getNameAndTypeIndex());
}
{
NameAndTypeInfo nameAndType = (NameAndTypeInfo) pool.getConstantInfo(13);
Assert.assertEquals(9, nameAndType.getIndex1());
Assert.assertEquals(14, nameAndType.getIndex2());
}
//抽查几个吧
{
MethodRefInfo methodRef = (MethodRefInfo)pool.getConstantInfo(45);
Assert.assertEquals(1, methodRef.getClassInfoIndex());
Assert.assertEquals(46, methodRef.getNameAndTypeIndex());
}
{
UTF8Info utf8Info = (UTF8Info) pool.getConstantInfo(53);
Assert.assertEquals("EmployeeV1.java", utf8Info.getValue());
}
}
@Test
public void testClassIndex(){
ClassIndex clzIndex = clzFile.getClzIndex();
ClassInfo thisClassInfo = (ClassInfo)clzFile.getConstantPool().getConstantInfo(clzIndex.getThisClassIndex());
ClassInfo superClassInfo = (ClassInfo)clzFile.getConstantPool().getConstantInfo(clzIndex.getSuperClassIndex());
Assert.assertEquals(FULL_QUALIFIED_CLASS_NAME, thisClassInfo.getClassName());
Assert.assertEquals("java/lang/Object", superClassInfo.getClassName());
}
private String byteToHexString(byte[] codes ){
StringBuffer buffer = new StringBuffer();
for(int i=0;i<codes.length;i++){
byte b = codes[i];
int value = b & 0xFF;
String strHex = Integer.toHexString(value);
if(strHex.length()< 2){
strHex = "0" + strHex;
}
buffer.append(strHex);
}
return buffer.toString();
}
/**
* 下面是第三次JVM课应实现的测试用例
*/
@Test
public void testReadFields(){
List<Field> fields = clzFile.getFields();
Assert.assertEquals(2, fields.size());
{
Field f = fields.get(0);
Assert.assertEquals("name:Ljava/lang/String;", f.toString());
}
{
Field f = fields.get(1);
Assert.assertEquals("age:I", f.toString());
}
}
@Test
public void testMethods(){
List<Method> methods = clzFile.getMethods();
ConstantPool pool = clzFile.getConstantPool();
{
Method m = methods.get(0);
assertMethodEquals(pool,m,
"<init>",
"(Ljava/lang/String;I)V",
"2ab7000c2a2bb5000f2a1cb50011b1");
}
{
Method m = methods.get(1);
assertMethodEquals(pool,m,
"setName",
"(Ljava/lang/String;)V",
"2a2bb5000fb1");
}
{
Method m = methods.get(2);
assertMethodEquals(pool,m,
"setAge",
"(I)V",
"2a1bb50011b1");
}
{
Method m = methods.get(3);
assertMethodEquals(pool,m,
"sayHello",
"()V",
"b2001c1222b60024b1");
}
{
Method m = methods.get(4);
assertMethodEquals(pool,m,
"main",
"([Ljava/lang/String;)V",
"bb000159122b101db7002d4c2bb6002fb1");
}
}
private void assertMethodEquals(ConstantPool pool,Method m , String expectedName, String expectedDesc,String expectedCode){
String methodName = pool.getUTF8String(m.getNameIndex());
String methodDesc = pool.getUTF8String(m.getDescriptorIndex());
String code = m.getCodeAttr().getCode();
Assert.assertEquals(expectedName, methodName);
Assert.assertEquals(expectedDesc, methodDesc);
Assert.assertEquals(expectedCode, code);
}
}