Develop Reference

Soot - Get JimpleBody from a CFG

I'd like to get UnitGraph from a Java Class.
I load it by ClassFile and get the method_info of main().
Then I create a CFG and try to convert it into a UnitGraph.
My method is to get JimpleBody of the CFG and then create a UnitGraph.
However, I can't get JimpleBody by invoking cfg.jimplify(...) since it throws the following error:
Exception in thread "main" java.lang.RuntimeException: no method associated w/ body
at soot.Body.getMethod(Body.java:137)
at soot.coffi.CFG.jimplify(CFG.java:814)
at com.LiveVariableAnalysis.main(LiveVariableAnalysis.java:151)
My code is as follows:
String mainClassName = "Calculate";
String mainClassPath = String.format("./target/test-classes/%s.class", mainClassName);
ClassFile mainClassFile = new ClassFile(mainClassName);
FileInputStream is = new FileInputStream(mainClassPath);
mainClassFile.loadClassFile(is);
logger.info(String.format("Loading Class: %s ...", mainClassFile));
method_info methodInfo = null;
for (method_info method: mainClassFile.methods) {
if (Objects.equals(method.toName(mainClassFile.constant_pool), "main")) {
methodInfo = method;
}
}
logger.info(String.format("Loading method_info: %s ...", methodInfo.toName(mainClassFile.constant_pool)));
mainClassFile.parseMethod(methodInfo);
CFG cfg = new CFG(methodInfo);
JimpleBody jimpleBody = new JimpleBody();
// Error occurs here
cfg.jimplify(mainClassFile.constant_pool, mainClassFile.this_class, mainClassFile.bootstrap_methods_attribute, jimpleBody);
UnitGraph unitGraph = new ClassicCompleteUnitGraph(jimpleBody);
logger.info(String.format("Creating unitGraph with %d units ...", unitGraph.size()));
I know there are other ways to create a UnitGraph, such as:
String mainClassName = "Calculate";
SootClass mainClass = Scene.v().loadClassAndSupport(className);
Scene.v().setMainClass(mainClass);
soot.Main.main(args);
SootClass mainClass = Scene.v().getMainClass();
String methodSignature = "void main(java.lang.String[])";
SootMethod mainMethod = mainClass.getMethod(methodSignature);
Body jimpleBody = mainMethod.retrieveActiveBody();
UnitGraph unitGraph = new ClassicCompleteUnitGraph(jimpleBody);
However, in this way, I need to set Scene.v().setSootClassPath(path) for jce.jar and rt.jar, which I don't want to occur in my code. So if there is another way I can get UnitGraph without setting such a path, please help me.

Although I still can't turn method_info into a SootMathod and then get a UnitGraph, I can use Options.v().set_prepend_classpath(true) to avoid set jce.jar and rt.jar dirctly. This also achieves my goal.

Correct way to instantiate a groovy class

I want to instatiate a groovy class and i have some concerns
My first choice is to use GroovyShell :
groovy-script:
class Foo {
public String doStuff(String stuff) {
return stuff + "_utils";
}
}
new Foo(); // ??
main-script :
GroovyShell shell = new GroovyShell();
Script script = shell.parse(new File(path));
def clazz = script.run();
String result = clazz.doStuff("test");
print(result); // test_utils;
The second option is to use GroovyClassLoader :
groovy-script
class Foo {
public String doStuff(String stuff) {
return stuff + "_utils";
}
}
main-script
GroovyClassLoader loader = new GroovyClassLoader();
Script script = loader.parseClass(new File(path))
Object clazz = script.newInstance();
Object[] args = new Object[1];
args[0] = "test";
String result = clazz.invokeMethod("doStuff", args);
print(result) // test_utils
Both will run fine, i would prefer to use GroovyShell because i use it everywhere in my current code, but i don't know if new Foo() inside my scripts can cause any memory leaks. Is it possible?

GroovyShell uses the default GroovyClassLoader. So if you don't need any extra specific features that are provided by GroovyClassLoader, you should stick to GroovyShell to keep it simple. GroovyShell and GroovyClassLoader are instances of garbage collected and I don't believe there are memory leaks for neither of them.

After #daggett's help i managed to find the solution that fits my needs.
I will not use groovy classes at all.
A simple example
utility groovy script :
String doStuff() {
return "doStuff";
}
String doStuff2(){
return "doStuff2";
}
calling the utility methods from the main groovy script
GroovyShell shell = new GroovyShell();
Script utilsScript = shell.parse(new File(PATH_TO_UTIL_SCRIPT));
String result = utilsScript.doStuff();
println(result); // doStuff;
String result2 = utilsScript.doStuff2();
println(result2); // doStuff2;
This is not the answer to the original question but since it fits my need i am fine.

Compile Groovy class at runtime in Java

I am successfully able to compile Groovy in Java at runtime and store it in a database and pull it out. I can't compile a Groovy class if it has inner classes or an inner enum. Has anyone successfully compiled Groovy code like this and included inner classes/enums and able to pull the script out by classname?
For example, I want to load the "Test" script shown below that contains inner classes and run the script at run time.
Compiler code:
public byte[] compileGroovyScript(final String className, final String script) {
byte[] compiledScriptBytes = null;
CompilationUnit compileUnit = new CompilationUnit();
compileUnit.addSource(className, script);
compileUnit.compile(Phases.CLASS_GENERATION);
for (Object compileClass : compileUnit.getClasses()) {
GroovyClass groovyClass = (GroovyClass) compileClass;
compiledScriptBytes = groovyClass.getBytes();
}
return compiledScriptBytes;
}
Code to pull script out:
public Class getGroovyScript(final String className, final byte[] script) {
Class clazz = null;
try (GroovyClassLoader classLoader = new GroovyClassLoader(this.getClass().getClassLoader())) {
clazz = classLoader.defineClass(className, script);
} catch (IOException e) {
} catch (Exception e) {
}
return clazz;
}
Code to run the script:
Class groovyClass = app.getGroovyScript(className, compiledScript);
TestScript script = (TestScript) groovyClass.newInstance();
System.out.println(script.getMessage());
Groovy script:
import com.groovy.groovy.TestScript
class Test implements TestScript {
String getMessage() {
[1..10].each(){
println it
}
return "Jello"
}
}

It isn't clear from the description why you are doing the compiling yourself. If you can just let Groovy do it for you then the whole thing can just be simplified to something like this:
String script = // string containing the script you want to parse
GroovyClassLoader groovyClassLoader = new GroovyClassLoader();
Class theParsedClass = groovyClassLoader.parseClass(script);

Ok this may be a little late but hopefully it helps the next person. I think you need to save a List for each groovy class and then cl.defineClass and finally cl.loadClass. I think groovy sometimes compile to a list of classes basically as in below when I addSource(), I add one class and then loop over all the generated classes from that one file.
This is the code I am currently running(though I have not tried saving and reloading at a later time)
GroovyClassLoader cl = new GroovyClassLoader();
CompilationUnit compileUnit = new CompilationUnit();
compileUnit.addSource(scriptCode.getClassName(), scriptCode.getScriptSourceCode());
compileUnit.compile(Phases.CLASS_GENERATION);
compileUnit.setClassLoader(cl);
GroovyClass target = null;
for (Object compileClass : compileUnit.getClasses()) {
GroovyClass groovyClass = (GroovyClass) compileClass;
cl.defineClass(groovyClass.getName(), groovyClass.getBytes());
if(groovyClass.getName().equals(scriptCode.getClassName())) {
target = groovyClass;
}
}
if(target == null)
throw new IllegalStateException("Could not find proper class");
return cl.loadClass(target.getName());
take note of the cl.defineClass call which puts the class in the classloader so when it is looked up(the enum or innerclass), it will be there.
and so now I think you do not need to create your own class loader(though you avoid useless defineClass until it is needed with your own classloader which can be useful and more performant).

This forgoes any error handling for the sake of simplicity here, but this is probably what you want:
public byte[] compileGroovyScript(final String className, final String script) {
byte[] compiledScriptBytes = null;
CompilationUnit compileUnit = new CompilationUnit();
compileUnit.addSource(className, script);
compileUnit.compile(Phases.CLASS_GENERATION);
List classes = compileUnit.getClasses();
GroovyClass firstClass = (GroovyClass)classes.get(0);
compiledScriptBytes = firstClass.getBytes();
return compiledScriptBytes;
}

Depending on your requirements, you might want to provide access to the inner classes and you could do that with something like this which finds the class with the matching name instead of assuming the first class:
public byte[] compileGroovyScript(final String className, final String script) {
byte[] compiledScriptBytes = null;
CompilationUnit compileUnit = new CompilationUnit();
compileUnit.addSource(className, script);
compileUnit.compile(Phases.CLASS_GENERATION);
for (Object compileClass : compileUnit.getClasses()) {
GroovyClass groovyClass = (GroovyClass) compileClass;
if(className.equals(groovyClass.getName())) {
compiledScriptBytes = groovyClass.getBytes();
break;
}
}
return compiledScriptBytes;
}

I am running into this myself but having just done an on-demand java compiler at runtime, I believe you are running into the same issue I solved in this code
https://github.com/deanhiller/webpieces/tree/master/runtimecompile/src/main/java/org/webpieces/compiler/api
webpieces/runtimecompile is a re-usable on-demand java compiler using the eclipse compiler.
Now, for groovy, I think you are running into this case
1. you compile ONE script
2. this results in 'multiple' class file objects (I think) just like mine did
3. This is where you need to store EACH in the database SEPARATELY
4. Then you need a classloader that tries to lookup the 'inner classes' when jvm asks for it
5. finally you do a yourclassLoader.loadApplicationClass (much like the one in CompileOnDemandImpl.java in the project above
6. To be clear, step 5 causes step 4 to happen behind the scenes (and that is what is confusing).
If you step through the test case AnonymousByteCacheTest, it pretty much is doing something like that.
you don't need to install ANYTHING to run the build on that project, just clone it and "./gradlew test" and will pass and "./gradlew eclipse" or "./gradlew idea" and it generates IDE files so you can step through it.
It is very very similar. I am trying to get the groovy version working next myself.

Getting return values from a compiled string which contains java codes in a java program using javaCompiler

I have been able to successfully call javaCompiler and even compiled a string that contains java codes as shown below.
public class CompilerAPITest {
final Logger logger = Logger.getLogger(CompilerAPITest.class.getName()) ;
/**Java source code to be compiled dynamically*/
static String sourceCode = "package com.accordess.ca; class DynamicCompilationHelloWorld{ public static String main (String args[]){ String str=\"The return value\"; return str ;}}";
/**
* Does the required object initialization and compilation.
*/
public void doCompilation (){
/*Creating dynamic java source code file object*/
SimpleJavaFileObject fileObject = new DynamicJavaSourceCodeObject ("com.accordess.ca.DynamicCompilationHelloWorld", sourceCode) ;
JavaFileObject javaFileObjects[] = new JavaFileObject[]{fileObject} ;
/*Instantiating the java compiler*/
JavaCompiler compiler = ToolProvider.getSystemJavaCompiler();
/**
* Retrieving the standard file manager from compiler object, which is used to provide
* basic building block for customizing how a compiler reads and writes to files.
*
* The same file manager can be reopened for another compiler task.
* Thus we reduce the overhead of scanning through file system and jar files each time
*/
StandardJavaFileManager stdFileManager = compiler.getStandardFileManager(null, Locale.getDefault(), null);
/* Prepare a list of compilation units (java source code file objects) to input to compilation task*/
Iterable<? extends JavaFileObject> compilationUnits = Arrays.asList(javaFileObjects);
/*Prepare any compilation options to be used during compilation*/
//In this example, we are asking the compiler to place the output files under bin folder.
String[] compileOptions = new String[]{"-d", "bin"} ;
Iterable<String> compilationOptionss = Arrays.asList(compileOptions);
/*Create a diagnostic controller, which holds the compilation problems*/
DiagnosticCollector<JavaFileObject> diagnostics = new DiagnosticCollector<JavaFileObject>();
/*Create a compilation task from compiler by passing in the required input objects prepared above*/
CompilationTask compilerTask = compiler.getTask(null, stdFileManager, diagnostics, compilationOptionss, null, compilationUnits) ;
//Perform the compilation by calling the call method on compilerTask object.
boolean status = compilerTask.call();
if (!status){//If compilation error occurs
/*Iterate through each compilation problem and print it*/
for (Diagnostic diagnostic : diagnostics.getDiagnostics()){
System.out.format("Error on line %d in %s", diagnostic.getLineNumber(), diagnostic);
}
}
try {
stdFileManager.close() ;//Close the file manager
} catch (IOException e) {
e.printStackTrace();
}
}
public static void main(String args[]){
new CompilerAPITest ().doCompilation() ;
System.out.println("Compilation is running");
}
}
The compiled class is even appearing in my bin folder. However i wanted to know if i could get the returned value directly from the compiler itself?

You can try to use Eclipse compiler
http://www.eclipse.org/jdt/core/index.php
This blog post might be useful.

Run java application from JSP page

The question on this page asks how to run a java program from a php page:
Run Java class file from PHP script on a website
I want to do the exact same thing from a JSP page. I don't want to import the classes and call functions or anything complicated like that. All I want to do is run a command like:
java Test
from a JSP page and then get whatever is printed out to System.out by Test saved in a variable in the JSP page.
How do I do this?
Thanks a lot!!

You can do this via Runtime.exec():
Process p = Runtime.getRuntime().exec("java Test");
BufferedReader input = new BufferedReader(new InputStreamReader(p.getInputStream()));
String line = input.readLine();
while (line != null) {
// process output of the command
// ...
}
input.close();
// wait for the command complete
p.waitFor();
int ret = p.exitValue();

Since you already have a JVM running you should be able to do it by instantiating a classloader with the jars and reflectively find the main method and invoke it.
This is some boilerplate that may be helpful:
// add the classes dir and each file in lib to a List of URLs.
List urls = new ArrayList();
urls.add(new File(CLASSES).toURL());
for (File f : new File(LIB).listFiles()) {
urls.add(f.toURL());
}
// feed your URLs to a URLClassLoader
ClassLoader classloader =
new URLClassLoader(
urls.toArray(new URL[0]),
ClassLoader.getSystemClassLoader().getParent());
// relative to that classloader, find the main class and main method
Class mainClass = classloader.loadClass("Test");
Method main = mainClass.getMethod("main",
new Class[]{args.getClass()});
// well-behaved Java packages work relative to the
// context classloader. Others don't (like commons-logging)
Thread.currentThread().setContextClassLoader(classloader);
// Invoke with arguments
String[] nextArgs = new String[]{ "hello", "world" }
main.invoke(null, new Object[] { nextArgs });