问题
I'm developing a web application where I can import a java code, compile and then execute it. This class might have some imports from another libraries, which I added to my classpath. Running it as a desktop application, it works, but running under wildfly 9.0.2 it doesn't find my classpath libs and so, I have errors to compile my code.
Do I have to change any setting on wildfly configuration? I tried my code with and without maven.
I'm using this lib to compile my code, and like I said, it worked using the app like desktop: https://github.com/trung/InMemoryJavaCompiler
Errors:
13:44:57,686 ERROR [stderr] (default task-5) /br/com/project/webtest/service/CompileClass.java:2: error: package org.junit does not exist
13:44:57,686 ERROR [stderr] (default task-5) import static org.junit.Assert.*;
13:44:57,686 ERROR [stderr] (default task-5) ^
13:44:57,687 ERROR [stderr] (default task-5) /br/com/project/webtest/service/CompileClass.java:3: error: cannot find symbol
13:44:57,687 ERROR [stderr] (default task-5) import br.com.project.webtest.service.SeleniumService;
13:44:57,688 ERROR [stderr] (default task-5) ^
13:44:57,688 ERROR [stderr] (default task-5) symbol: class SeleniumService
13:44:57,688 ERROR [stderr] (default task-5) location: package br.com.project.webtest.service
13:44:57,689 ERROR [stderr] (default task-5) /br/com/project/webtest/service/CompileClass.java:4: error: package org.junit does not exist
13:44:57,689 ERROR [stderr] (default task-5) import org.junit.*;
The error messages continues with all others import libs and then, the classformaterror:
13:44:57,751 WARNING [javax.enterprise.resource.webcontainer.jsf.lifecycle] (default task-5) #{testController.action()}: java.lang.ClassFormatError: Truncated class file: javax.faces.FacesException: #{testController.action()}: java.lang.ClassFormatError: Truncated class file
Edit: I added using eclipse mars, under the Webcontent/web-inf/lib folder, added my libs and right click, add to build path.
Edit 2: Class responsible for creating the code and get the result:
package br.com.test;
import java.io.IOException;
import java.nio.charset.Charset;
import java.nio.file.Files;
import java.nio.file.Paths;
import javax.faces.bean.ManagedBean;
import javax.faces.bean.SessionScoped;
@ManagedBean
@SessionScoped
public class TestController {
public void actionParent() {
String javaCode = generateJavaCode();
Class<?> compile = null;
try {
compile = InMemoryCompilerTest.compile(Thread.currentThread().getContextClassLoader(),
"br.com.project.webtest.service.CompileClass", javaCode);
System.out.println("Worked: " + compile);
} catch (Exception e) {
e.printStackTrace();
}
}
public void actionClassLoader() {
String javaCode = generateJavaCode();
Class<?> compile = null;
try {
compile = InMemoryCompilerTest.compile("br.com.project.webtest.service.CompileClass", javaCode);
System.out.println("Worked: " + compile);
} catch (Exception e) {
e.printStackTrace();
}
}
static String readFile(String path, Charset encoding) throws IOException {
byte[] encoded = Files.readAllBytes(Paths.get(path));
return new String(encoded, encoding);
}
private static String generateJavaCode() {
String java = "package br.com.project.webtest.service;\r\n"
+ "import static org.junit.Assert.*;\r\n"
+ "public class CompileClass {\r\n"
+ " public CompileClass() {\r\n"
+ " System.out.println(\"Dynamically compiled\");\r\n"
+ " String text = \"Testing JUnit lib\";\r\n"
+ " assertEquals(\"Testing JUnit lib\", text);\r\n"
+ " System.out.println(\"completed\");\r\n"
+ " }\r\n" + " public static void main(String[] args) {\r\n"
+ " new CompileClass();\r\n"
+ " System.out.println(\"finish\");\r\n"
+ " }\r\n"
+ "}\r\n";
return java;
}
public static void main(String[] args) {
TestController c = new TestController();
c.actionClassLoader();
c.actionParent();
}
}
I created a class which extends the lib and changed use parent classloader:
public class InMemoryCompilerTest extends InMemoryJavaCompiler {
static JavaCompiler javac = ToolProvider.getSystemJavaCompiler();
public static Class<?> compile(ClassLoader parent, String className, String sourceCodeInText) throws Exception {
SourceCode sourceCode = new SourceCode(className, sourceCodeInText);
CompiledCode compiledCode = new CompiledCode(className);
Iterable<? extends JavaFileObject> compilationUnits = Arrays.asList(sourceCode);
DynamicClassLoader cl = new DynamicClassLoader(parent);
ExtendedStandardJavaFileManager fileManager = new ExtendedStandardTest(
javac.getStandardFileManager(null, null, null), compiledCode, cl);
JavaCompiler.CompilationTask task = javac.getTask(null, fileManager, null, null, null, compilationUnits);
boolean result = task.call();
return cl.loadClass(className);
}
}
public class ExtendedStandardTest extends ExtendedStandardJavaFileManager{
protected ExtendedStandardTest(JavaFileManager fileManager, CompiledCode compiledCode, DynamicClassLoader cl) {
super(fileManager, compiledCode, cl);
}
}
xhtml:
<html xmlns="http://www.w3.org/1999/xhtml" xmlns:ui="http://java.sun.com/jsf/facelets" xmlns:f="http://java.sun.com/jsf/core" xmlns:h="http://java.sun.com/jsf/html">
<h:head></h:head>
<h:body>
<h:form>
<h:commandButton action="#{testController.actionClassLoader()}" value="ClassLoader" />
<h:commandButton action="#{testController.actionParent()}" value="Parent" />
</h:form>
</h:body>
</html>
I tested passing parent classloader as you sugested but also didnt work.
The first class "TestController" executing from main method it works.
Edit:
I have added the following code where I can set the classpath with my libs:
// set the classpath
List<String> options = new ArrayList<String>();
options.add("-classpath");
StringBuilder sb = new StringBuilder();
URLClassLoader urlClassLoader = (URLClassLoader) parent;
for (URL url : urlClassLoader.getURLs()) {
sb.append(url.getFile()).append(File.pathSeparator);
}
options.add(sb.toString());
Executing as a Java application it returns:
[-classpath, /C:/Users/dev/Automacao/workspace/test/build/classes/;/C:/Users/dev/Automacao/workspace/test/WebContent/WEB-INF/lib/InMemoryJavaCompiler-1.2.jar;/C:/Users/dev/Automacao/workspace/test/WebContent/WEB-INF/lib/commons-io-2.5.jar;/C:/Users/dev/Automacao/workspace/test/WebContent/WEB-INF/lib/workspace_libs/client-combined-3.0.0-beta3-nodeps.jar;/C:/Users/dev/Automacao/workspace/test/WebContent/WEB-INF/lib/workspace_libs/commons-codec-1.10.jar;/C:/Users/dev/Automacao/workspace/test/WebContent/WEB-INF/lib/workspace_libs/commons-exec-1.3.jar;/C:/Users/dev/Automacao/workspace/test/WebContent/WEB-INF/lib/workspace_libs/commons-logging-1.2.jar;/C:/Users/dev/Automacao/workspace/test/WebContent/WEB-INF/lib/workspace_libs/gson-2.3.1.jar;/C:/Users/dev/Automacao/workspace/test/WebContent/WEB-INF/lib/workspace_libs/guava-19.0.jar;/C:/Users/dev/Automacao/workspace/test/WebContent/WEB-INF/lib/workspace_libs/hamcrest-core-1.3.jar;/C:/Users/dev/Automacao/workspace/test/WebContent/WEB-INF/lib/workspace_libs/hamcrest-library-1.3.jar;/C:/Users/dev/Automacao/workspace/test/WebContent/WEB-INF/lib/workspace_libs/httpclient-4.5.2.jar;/C:/Users/dev/Automacao/workspace/test/WebContent/WEB-INF/lib/workspace_libs/httpcore-4.4.4.jar;/C:/Users/dev/Automacao/workspace/test/WebContent/WEB-INF/lib/workspace_libs/httpmime-4.5.2.jar;/C:/Users/dev/Automacao/workspace/test/WebContent/WEB-INF/lib/workspace_libs/jna-4.1.0.jar;/C:/Users/dev/Automacao/workspace/test/WebContent/WEB-INF/lib/workspace_libs/jna-platform-4.1.0.jar;/C:/Users/dev/Automacao/workspace/test/WebContent/WEB-INF/lib/workspace_libs/junit-4.12.jar;/C:/Users/dev/Automacao/workspace/test/WebContent/WEB-INF/lib/workspace_libs/netty-3.5.7.Final.jar;/C:/Users/dev/Automacao/workspace/test/WebContent/WEB-INF/lib/workspace_libs/phantomjsdriver-1.3.0.jar;/C:/Users/dev/Automacao/workspace/test/WebContent/WEB-INF/lib/workspace_libs/cglib-nodep-3.2.4.jar;/C:/Program%20Files/Apache%20Software%20Foundation/Apache%20Tomcat%208.0.3/lib/annotations-api.jar;/C:/Program%20Files/Apache%20Software%20Foundation/Apache%20Tomcat%208.0.3/lib/catalina-ant.jar;/C:/Program%20Files/Apache%20Software%20Foundation/Apache%20Tomcat%208.0.3/lib/catalina-ha.jar;/C:/Program%20Files/Apache%20Software%20Foundation/Apache%20Tomcat%208.0.3/lib/catalina-storeconfig.jar;/C:/Program%20Files/Apache%20Software%20Foundation/Apache%20Tomcat%208.0.3/lib/catalina-tribes.jar;/C:/Program%20Files/Apache%20Software%20Foundation/Apache%20Tomcat%208.0.3/lib/catalina.jar;/C:/Program%20Files/Apache%20Software%20Foundation/Apache%20Tomcat%208.0.3/lib/ecj-4.3.1.jar;/C:/Program%20Files/Apache%20Software%20Foundation/Apache%20Tomcat%208.0.3/lib/el-api.jar;/C:/Program%20Files/Apache%20Software%20Foundation/Apache%20Tomcat%208.0.3/lib/jasper-el.jar;/C:/Program%20Files/Apache%20Software%20Foundation/Apache%20Tomcat%208.0.3/lib/jasper.jar;/C:/Program%20Files/Apache%20Software%20Foundation/Apache%20Tomcat%208.0.3/lib/jsp-api.jar;/C:/Program%20Files/Apache%20Software%20Foundation/Apache%20Tomcat%208.0.3/lib/servlet-api.jar;/C:/Program%20Files/Apache%20Software%20Foundation/Apache%20Tomcat%208.0.3/lib/tomcat-api.jar;/C:/Program%20Files/Apache%20Software%20Foundation/Apache%20Tomcat%208.0.3/lib/tomcat-coyote.jar;/C:/Program%20Files/Apache%20Software%20Foundation/Apache%20Tomcat%208.0.3/lib/tomcat-dbcp.jar;/C:/Program%20Files/Apache%20Software%20Foundation/Apache%20Tomcat%208.0.3/lib/tomcat-i18n-es.jar;/C:/Program%20Files/Apache%20Software%20Foundation/Apache%20Tomcat%208.0.3/lib/tomcat-i18n-fr.jar;/C:/Program%20Files/Apache%20Software%20Foundation/Apache%20Tomcat%208.0.3/lib/tomcat-i18n-ja.jar;/C:/Program%20Files/Apache%20Software%20Foundation/Apache%20Tomcat%208.0.3/lib/tomcat-jdbc.jar;/C:/Program%20Files/Apache%20Software%20Foundation/Apache%20Tomcat%208.0.3/lib/tomcat-jni.jar;/C:/Program%20Files/Apache%20Software%20Foundation/Apache%20Tomcat%208.0.3/lib/tomcat-spdy.jar;/C:/Program%20Files/Apache%20Software%20Foundation/Apache%20Tomcat%208.0.3/lib/tomcat-util-scan.jar;/C:/Program%20Files/Apache%20Software%20Foundation/Apache%20Tomcat%208.0.3/lib/tomcat-util.jar;/C:/Program%20Files/Apache%20Software%20Foundation/Apache%20Tomcat%208.0.3/lib/tomcat-websocket.jar;/C:/Program%20Files/Apache%20Software%20Foundation/Apache%20Tomcat%208.0.3/lib/websocket-api.jar;/C:/Users/dev/Automacao/workspace/libraries/JSF%202.2%20(Mojarra%202.2.0)/mojarra-2.2.0-FCS/lib/javax.faces.jar;]
Executing as webapplication:
[-classpath, /C:/Users/dev/Automacao/workspace/.metadata/.plugins/org.eclipse.wst.server.core/tmp0/wtpwebapps/test/WEB-INF/classes/;/C:/Users/dev/Automacao/workspace/.metadata/.plugins/org.eclipse.wst.server.core/tmp0/wtpwebapps/test/WEB-INF/lib/commons-io-2.5.jar;/C:/Users/dev/Automacao/workspace/.metadata/.plugins/org.eclipse.wst.server.core/tmp0/wtpwebapps/test/WEB-INF/lib/InMemoryJavaCompiler-1.2.jar;/C:/Users/dev/Automacao/workspace/.metadata/.plugins/org.eclipse.wst.server.core/tmp0/wtpwebapps/test/WEB-INF/lib/javax.faces.jar;]
How could I get the same result?
回答1:
Get it working.
I have to make that change mentioned by @NicolasFilotto, to use parent classloader when using a webapp. After that, for JavaCompiler works, as I'm using external libraries it's necessary to pass my classpath like mentioned on my last edit. Basically the code changed to:
public static Class<?> compile(ClassLoader parent, String className, String sourceCodeInText) throws Exception {
SourceCode sourceCode = new SourceCode(className, sourceCodeInText);
CompiledCode compiledCode = new CompiledCode(className);
Iterable<? extends JavaFileObject> compilationUnits = Arrays.asList(sourceCode);
DynamicClassLoader cl = new DynamicClassLoader(parent);
ExtendedStandardJavaFileManager fileManager = new ExtendedStandard(
javac.getStandardFileManager(null, null, null), compiledCode, cl);
// set the classpath
List<String> options = new ArrayList<String>();
options.add("-classpath");
StringBuilder sb = new StringBuilder();
Enumeration<URL> resources = parent.getResources("/");
while (resources.hasMoreElements()) {
URL url = resources.nextElement();
sb.append(url.getFile()).append(File.pathSeparator);
}
options.add(sb.toString());
// execute the compiler
Boolean call = javac.getTask(null, fileManager, null, options, null, compilationUnits).call();
if (call) {
return cl.loadClass(className);
}
return null;
}
Using wildfly I had to change URLClassLoader urlClassLoader = (URLClassLoader) parent; to Enumeration<URL> resources = parent.getResources("/");
回答2:
@VictorBello I already implements these features in Dynamic Loader. Even you can include Jar at run time in Dynamic Loader
public void DynamicJarCodeTest() throws Exception {
try {
StringBuilder sourceCode = new StringBuilder();
sourceCode.append("package org.dvare.dynamic;\n");
sourceCode.append("import org.apache.commons.math3.Field;\n");
sourceCode.append("public class SourceClass {\n");
sourceCode.append(" public String test() { \n");
sourceCode.append(" return \"inside test method\";\n");
sourceCode.append(" }\n");
sourceCode.append("}");
DynamicCompiler dynamicCompiler = new DynamicCompiler();
dynamicCompiler.setSeparateContext(true);
dynamicCompiler.setUpdateContextClassLoader(false);
dynamicCompiler.addJar(getClass().getClassLoader().getResource("commons-math3.jar"));
dynamicCompiler.addSource("org.dvare.dynamic.SourceClass", sourceCode.toString());
dynamicCompiler.build();
Class aClass = Class.forName("org.apache.commons.math3.Field", false, dynamicCompiler.getClassLoader());
Assert.assertNotNull(aClass);
Class bClass = Class.forName("org.dvare.dynamic.SourceClass", false, dynamicCompiler.getClassLoader());
Assert.assertNotNull(bClass);
} catch (DynamicCompilerException e) {
System.out.println(e.getErrorList());
} catch (Exception e) {
e.printStackTrace();
}
}
回答3:
Thanks to @victor-bello for the great solution. My solution looks like this:
- Need to copy all jar from your maven repository into one folder and distribute that folder with your app:
- From them generate classpath for javac (stupid way):
Copy InMemoryJavaCompiler code source from github and override:
public class InMemoryCompilerTest extends InMemoryJavaCompiler {
static JavaCompiler javac = ToolProvider.getSystemJavaCompiler(); public static Class<?> compile(ClassLoader parent, String className, String sourceCodeInText, String classpath ) throws Exception { SourceCode sourceCode = new SourceCode(className, sourceCodeInText); CompiledCode compiledCode = new CompiledCode(className); Iterable<? extends JavaFileObject> compilationUnits = Arrays.asList(sourceCode); DynamicClassLoader cl = new DynamicClassLoader(parent); ExtendedStandardJavaFileManager fileManager = new ExtendedStandard(javac.getStandardFileManager(null, null, null), compiledCode, cl); // set the classpath List<String> options = new ArrayList<String>(); options.add("-classpath"); options.add(classpath); // execute the compiler Boolean call = javac.getTask(null, fileManager, null, options, null, compilationUnits).call(); if (call) { return cl.loadClass(className); } return null; }}
Call compile method:
Class testClass = inMemoryCompilerTest.compile(Thread.currentThread().getContextClassLoader(),"com.namespace.here.ClassName", someCode, stringBuilder.toString());
来源：https://stackoverflow.com/questions/39796527/compile-dynamically-java-class-web-project