package test.loader;
import loader.ClassFileLoader;
import org.junit.After;
import org.junit.Assert;
import org.junit.Before;
import org.junit.Test;
public class ClassFileLoaderTest {
static String path1 = "D:\\JavaProject\\4week_minijvm\\out\\production\\4week_minijvm";
static String path2 = "D:\\temp";
@Before
public void before() throws Exception {
}
@After
public void after() throws Exception {
}
/**
*
* Method: readBinaryCode(String className)
*
*/
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 = "test.loader.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(1056, byteCodes.length);
}
@Test
public void testMagicNumber(){
ClassFileLoader loader = new ClassFileLoader();
loader.addClassPath(path1);
String className = "test.loader.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);
}
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();
}
}