// throws NotFoundException if fails to get names
// (for example when class of method argument type has not been loaded by class loader)
private String generateMethodKey(CtMethod method) throws NotFoundException {
String classQualifiedName = method.getDeclaringClass().getName();
String methodSimpleName = method.getName();
List<String> argClassQualifiedNames = getArgClassQualifiedNames(method);
return TestMethod.generateMethodKey(
classQualifiedName, methodSimpleName, argClassQualifiedNames);
}
@Override
public byte[] transform(
ClassLoader loader,
String className,
Class<?> classBeingRedefined,
ProtectionDomain protectionDomain,
byte[] classfileBuffer)
throws IllegalClassFormatException {
// Don't transform system classes. This reason is:
// - To improve performance
// - To avoid unexpected behaviors.
// For example, if transforms java.lang.invoke.** classes in Java8
// even without any ctClass modification, the classes become broken
// and Java stream API call fails unexpectedly.
// Maybe this is because CtClass instance generated by ClassPool.makeClass method
// is cached on global default ClassPool instance.
if (isJavaSystemClassName(className)) {
return null;
}
// TODO don't need to do anything for java package classes
ClassPool classPool = ClassPool.getDefault();
String hookClassName = HookMethodDef.class.getCanonicalName();
String initializeSrc = hookInitializeSrc();
boolean transformed = false;
InputStream stream = null;
try {
stream = new ByteArrayInputStream(classfileBuffer);
CtClass ctClass = null;
try {
ctClass = classPool.makeClass(stream, true);
} catch (RuntimeException e) {
// makeClass raises RuntimeException when the existing class is frozen.
// Since frozen classes are maybe system class, just ignore this exception
return null;
}
for (Pair<CtMethod, TestMethod> pair : allSubMethods(srcTree, ctClass)) {
CtMethod ctSubMethod = pair.getLeft();
TestMethod subMethod = pair.getRight();
if (ctSubMethod.isEmpty()) {
logger.info("skip empty method: " + ctSubMethod.getLongName());
continue; // cannot hook empty method
}
String subClassQualifiedName = subMethod.getTestClass().getQualifiedName();
String subMethodSimpleName = subMethod.getSimpleName();
String subMethodArgClassesStr =
TestMethod.argClassQualifiedNamesToArgClassesStr(
getArgClassQualifiedNames(ctSubMethod));
for (int i = 0; i < subMethod.getCodeBody().size(); i++) {
CodeLine codeLine = subMethod.getCodeBody().get(i);
if (i + 1 < subMethod.getCodeBody().size()) {
CodeLine nextCodeLine = subMethod.getCodeBody().get(i + 1);
assert codeLine.getEndLine() <= nextCodeLine.getStartLine();
if (codeLine.getEndLine() == nextCodeLine.getStartLine()) {
// - if multiple statements exist on a line, insert hook only after the last statement
// - avoid insertion at the middle of the statement.
// The problem happens when multi-line statements are like:
// method(1);method(
// 2);
continue;
}
}
// Hook should be inserted just after the code has finished
// since the code inserted by the insertAt method is inserted just before the specified
// line.
int insertedLine = subMethod.getCodeBody().get(i).getEndLine() + 1;
int actualInsertedLine = ctSubMethod.insertAt(insertedLine, false, null);
ctSubMethod.insertAt(
insertedLine,
String.format(
"%s%s.beforeCodeLineHook(\"%s\",\"%s\",\"%s\",\"%s\",%d, %d);",
initializeSrc,
hookClassName,
subClassQualifiedName,
subMethodSimpleName,
subMethodSimpleName,
subMethodArgClassesStr,
codeLine.getStartLine(),
actualInsertedLine));
transformed = true;
}
}
CtClass exceptionType = classPool.get(Throwable.class.getCanonicalName());
for (Pair<CtMethod, TestMethod> pair : allRootMethods(srcTree, ctClass)) {
CtMethod ctRootMethod = pair.getLeft();
TestMethod rootMethod = pair.getRight();
if (ctRootMethod.isEmpty()) {
continue; // cannot hook empty method
}
String rootClassQualifiedName = rootMethod.getTestClass().getQualifiedName();
String rootMethodSimpleName = rootMethod.getSimpleName();
String rootMethodArgClassesStr =
TestMethod.argClassQualifiedNamesToArgClassesStr(
getArgClassQualifiedNames(ctRootMethod));
for (int i = 0; i < rootMethod.getCodeBody().size(); i++) {
CodeLine codeLine = rootMethod.getCodeBody().get(i);
if (i + 1 < rootMethod.getCodeBody().size()) {
CodeLine nextCodeLine = rootMethod.getCodeBody().get(i + 1);
assert codeLine.getEndLine() <= nextCodeLine.getStartLine();
if (codeLine.getEndLine() == nextCodeLine.getStartLine()) {
// - if multiple statements exist on a line, insert hook only after the last statement
// - avoid insertion at the middle of the statement.
// The problem happens when multi-line statements are like:
// method(1);method(
// 2);
continue;
// TODO screen capture is not taken correctly for multiple statements in a line
}
}
// Hook should be inserted just after the code has finished
// since the code inserted by the insertAt method is inserted just before the specified
// line.
int insertedLine = rootMethod.getCodeBody().get(i).getEndLine() + 1;
int actualInsertedLine = ctRootMethod.insertAt(insertedLine, false, null);
ctRootMethod.insertAt(
insertedLine,
String.format(
"%s%s.beforeCodeLineHook(\"%s\",\"%s\",\"%s\",\"%s\",%d,%d);",
initializeSrc,
hookClassName,
rootClassQualifiedName,
rootMethodSimpleName,
rootMethodSimpleName,
rootMethodArgClassesStr,
codeLine.getStartLine(),
actualInsertedLine));
}
ctRootMethod.insertBefore(
String.format(
"%s%s.beforeMethodHook(\"%s\",\"%s\",\"%s\");",
initializeSrc,
hookClassName,
rootClassQualifiedName,
rootMethodSimpleName,
rootMethodSimpleName));
ctRootMethod.addCatch(
String.format(
"{ %s%s.methodErrorHook(\"%s\",\"%s\",$e); throw $e; }",
initializeSrc, hookClassName, rootClassQualifiedName, rootMethodSimpleName),
exceptionType);
ctRootMethod.insertAfter(
String.format(
"%s%s.afterMethodHook(\"%s\",\"%s\");",
initializeSrc, hookClassName, rootClassQualifiedName, rootMethodSimpleName),
true);
transformed = true;
}
// don't transform not changed ctClass
// (to improve performance and avoid unexpected error)
if (transformed) {
logger.info("transform " + className);
return ctClass.toBytecode();
} else {
return null;
}
} catch (CannotCompileException e) {
// print error since exception in transform method is just ignored
System.err.println("exception on " + className);
e.printStackTrace();
throw new IllegalClassFormatException(e.getLocalizedMessage());
} catch (Exception e) {
// print error since exception in transform method is just ignored
System.err.println("exception on " + className);
e.printStackTrace();
throw new RuntimeException(e);
} finally {
IOUtils.closeQuietly(stream);
}
}