plugins/org.eclipse.ease.lang.python/src/org/eclipse/ease/lang/python/PythonCodeFactory.java - ease/org.eclipse.ease.core - Git at Google

 /*******************************************************************************
  * Copyright (c) 2013, 2016 Atos and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v2.0
  * which accompanies this distribution, and is available at
  * https://www.eclipse.org/legal/epl-2.0/
  *
  * Contributors:
  *     Arthur Daussy - initial implementation
  *     Christian Pontesegger - simplified to use base class
  *******************************************************************************/
 package org.eclipse.ease.lang.python;

 import java.lang.reflect.Field;
 import java.lang.reflect.Method;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.List;
 import java.util.stream.Collectors;

 import org.eclipse.ease.AbstractCodeFactory;
 import org.eclipse.ease.Logger;
 import org.eclipse.ease.modules.EnvironmentModule;
 import org.eclipse.ease.modules.IEnvironment;
 import org.eclipse.ease.modules.ModuleHelper;
 import org.eclipse.ease.tools.StringTools;

 public class PythonCodeFactory extends AbstractCodeFactory {

 	public static List<String> RESERVED_KEYWORDS = new ArrayList<>();

 	static {
 		RESERVED_KEYWORDS.add("and");
 		RESERVED_KEYWORDS.add("as");
 		RESERVED_KEYWORDS.add("assert");
 		RESERVED_KEYWORDS.add("break");
 		RESERVED_KEYWORDS.add("class");
 		RESERVED_KEYWORDS.add("continue");
 		RESERVED_KEYWORDS.add("def");
 		RESERVED_KEYWORDS.add("del");
 		RESERVED_KEYWORDS.add("elif");
 		RESERVED_KEYWORDS.add("else");
 		RESERVED_KEYWORDS.add("except");
 		RESERVED_KEYWORDS.add("exec");
 		RESERVED_KEYWORDS.add("finally");
 		RESERVED_KEYWORDS.add("for");
 		RESERVED_KEYWORDS.add("from");
 		RESERVED_KEYWORDS.add("global");
 		RESERVED_KEYWORDS.add("if");
 		RESERVED_KEYWORDS.add("import");
 		RESERVED_KEYWORDS.add("in");
 		RESERVED_KEYWORDS.add("is");
 		RESERVED_KEYWORDS.add("lambda");
 		RESERVED_KEYWORDS.add("not");
 		RESERVED_KEYWORDS.add("or");
 		RESERVED_KEYWORDS.add("pass");
 		RESERVED_KEYWORDS.add("print");
 		RESERVED_KEYWORDS.add("raise");
 		RESERVED_KEYWORDS.add("return");
 		RESERVED_KEYWORDS.add("try");
 		RESERVED_KEYWORDS.add("while");
 		RESERVED_KEYWORDS.add("with");
 		RESERVED_KEYWORDS.add("yield");

 		// built in functions
 		RESERVED_KEYWORDS.add("__import__");
 		RESERVED_KEYWORDS.add("abs");
 		RESERVED_KEYWORDS.add("all");
 		RESERVED_KEYWORDS.add("any");
 		RESERVED_KEYWORDS.add("ascii");
 		RESERVED_KEYWORDS.add("bin");
 		RESERVED_KEYWORDS.add("bool");
 		RESERVED_KEYWORDS.add("bytearray");
 		RESERVED_KEYWORDS.add("bytes");
 		RESERVED_KEYWORDS.add("callable");
 		RESERVED_KEYWORDS.add("chr");
 		RESERVED_KEYWORDS.add("classmethod");
 		RESERVED_KEYWORDS.add("compile");
 		RESERVED_KEYWORDS.add("complex");
 		RESERVED_KEYWORDS.add("delattr");
 		RESERVED_KEYWORDS.add("dict");
 		RESERVED_KEYWORDS.add("dir");
 		RESERVED_KEYWORDS.add("divmod");
 		RESERVED_KEYWORDS.add("enumerate");
 		RESERVED_KEYWORDS.add("eval");
 		RESERVED_KEYWORDS.add("exec");
 		RESERVED_KEYWORDS.add("filter");
 		RESERVED_KEYWORDS.add("float");
 		RESERVED_KEYWORDS.add("format");
 		RESERVED_KEYWORDS.add("frozenset");
 		RESERVED_KEYWORDS.add("getattr");
 		RESERVED_KEYWORDS.add("globals");
 		RESERVED_KEYWORDS.add("hasattr");
 		RESERVED_KEYWORDS.add("hash");
 		RESERVED_KEYWORDS.add("help");
 		RESERVED_KEYWORDS.add("hex");
 		RESERVED_KEYWORDS.add("id");
 		RESERVED_KEYWORDS.add("input");
 		RESERVED_KEYWORDS.add("int");
 		RESERVED_KEYWORDS.add("isinstance");
 		RESERVED_KEYWORDS.add("issubclass");
 		RESERVED_KEYWORDS.add("iter");
 		RESERVED_KEYWORDS.add("len");
 		RESERVED_KEYWORDS.add("list");
 		RESERVED_KEYWORDS.add("locals");
 		RESERVED_KEYWORDS.add("map");
 		RESERVED_KEYWORDS.add("max");
 		RESERVED_KEYWORDS.add("memoryview");
 		RESERVED_KEYWORDS.add("min");
 		RESERVED_KEYWORDS.add("next");
 		RESERVED_KEYWORDS.add("object");
 		RESERVED_KEYWORDS.add("oct");
 		RESERVED_KEYWORDS.add("open");
 		RESERVED_KEYWORDS.add("ord");
 		RESERVED_KEYWORDS.add("pow");
 		RESERVED_KEYWORDS.add("print");
 		RESERVED_KEYWORDS.add("property");
 		RESERVED_KEYWORDS.add("range");
 		RESERVED_KEYWORDS.add("repr");
 		RESERVED_KEYWORDS.add("reversed");
 		RESERVED_KEYWORDS.add("round");
 		RESERVED_KEYWORDS.add("set");
 		RESERVED_KEYWORDS.add("setattr");
 		RESERVED_KEYWORDS.add("slice");
 		RESERVED_KEYWORDS.add("sorted");
 		RESERVED_KEYWORDS.add("staticmethod");
 		RESERVED_KEYWORDS.add("str");
 		RESERVED_KEYWORDS.add("sum");
 		RESERVED_KEYWORDS.add("super");
 		RESERVED_KEYWORDS.add("tuple");
 		RESERVED_KEYWORDS.add("type");
 		RESERVED_KEYWORDS.add("vars");
 		RESERVED_KEYWORDS.add("zip");
 	}

 	private static String toSafeNameStatic(String name) {
 		while (RESERVED_KEYWORDS.contains(name))
 			name = name + "_";

 		return name;
 	}

 	@Override
 	protected String toSafeName(String name) {
 		return toSafeNameStatic(name);
 	}

 	@Override
 	protected String createFieldWrapper(IEnvironment environment, String identifier, Field field) {
 		final StringBuilder pythonCode = new StringBuilder();

 		pythonCode.append("import sys").append(StringTools.LINE_DELIMITER);

 		pythonCode.append("if \"py4j\" in sys.modules:").append(StringTools.LINE_DELIMITER);
 		pythonCode.append("    ");
 		pythonCode.append(field.getName());
 		pythonCode.append(" = py4j.java_gateway.get_field(");
 		pythonCode.append(identifier);
 		pythonCode.append(", \"");
 		pythonCode.append(field.getName());
 		pythonCode.append("\")");
 		pythonCode.append(StringTools.LINE_DELIMITER);

 		pythonCode.append("else:").append(StringTools.LINE_DELIMITER);
 		pythonCode.append("    ");
 		pythonCode.append(field.getName());
 		pythonCode.append(" = ");
 		pythonCode.append(identifier);
 		pythonCode.append(".");
 		pythonCode.append(field.getName());
 		pythonCode.append(StringTools.LINE_DELIMITER);

 		return pythonCode.toString();
 	}

 	@Override
 	public String createFunctionWrapper(IEnvironment environment, final String moduleVariable, final Method method) {

 		final StringBuilder pythonCode = new StringBuilder();

 		// parse parameters
 		final List<Parameter> parameters = ModuleHelper.getParameters(method);

 		// build parameter string
 		final StringBuilder methodSignature = new StringBuilder();
 		final StringBuilder methodCall = new StringBuilder();

 		for (final Parameter parameter : parameters) {
 			methodSignature.append(", ").append(toSafeName(parameter.getName()));
 			methodCall.append(", ").append(toSafeName(parameter.getName()));
 			if (parameter.isOptional())
 				methodSignature.append(" = ").append(getDefaultValue(parameter));
 		}

 		if (methodSignature.length() > 2) {
 			methodSignature.delete(0, 2);
 			methodCall.delete(0, 2);
 		}

 		final String body = buildMethodBody(parameters, method, moduleVariable, environment);

 		// build function declarations
 		for (final String name : getMethodNames(method)) {
 			if (!isValidMethodName(name)) {
 				Logger.error(Activator.PLUGIN_ID,
 						"The method name \"" + name + "\" from the module \"" + moduleVariable + "\" can not be wrapped because it's name is reserved");

 			} else if (!name.isEmpty()) {
 				pythonCode.append("def ").append(name).append('(').append(methodSignature).append("):\n");
 				pythonCode.append(indent(body, "    "));
 				pythonCode.append('\n');
 				pythonCode.append(name).append(".__ease__ = True\n");
 				pythonCode.append('\n');
 			}
 		}

 		return pythonCode.toString();
 	}

 	private String buildMethodBody(List<Parameter> parameters, Method method, String classIdentifier, IEnvironment environment) {
 		final StringBuilder body = new StringBuilder();

 		final String methodId = ((EnvironmentModule) environment).registerMethod(method);

 		// insert deprecation warnings
 		if (ModuleHelper.isDeprecated(method))
 			body.append("printError(\"" + method.getName() + "() is deprecated. Consider updating your code.\")").append(StringTools.LINE_DELIMITER);

 		// Convert Lists to Java arrays
 		body.append(buildArrayConversions(parameters)).append(StringTools.LINE_DELIMITER);

 		// check for callbacks
 		body.append("if not ").append(EnvironmentModule.getWrappedVariableName(environment)).append(".hasMethodCallback(\"").append(methodId).append("\"):")
 				.append(StringTools.LINE_DELIMITER);

 		// simple execution
 		body.append("    return ").append(classIdentifier).append(".").append(method.getName()).append("(").append(buildParameterList(parameters)).append(")")
 				.append(StringTools.LINE_DELIMITER);
 		body.append(StringTools.LINE_DELIMITER);

 		// execution with callbacks
 		body.append("else:").append(StringTools.LINE_DELIMITER);
 		if (environment.getScriptEngine().getDescription().getID().startsWith("org.eclipse.ease.lang.python.py4j")) {
 			// special handling for Py4J as it cannot use java varargs parameters directly
 			body.append("    ").append("parameters_array = gateway.new_array(gateway.jvm.Object, ").append(parameters.size()).append(")")
 					.append(StringTools.LINE_DELIMITER);
 			for (int index = 0; index < parameters.size(); index++) {
 				// Py4J cannot execute
 				// gateway.new_array(gateway.jvm.Object, 1)[0] = None
 				// as the default value for array elements is null anyway, we simply do not set those
 				body.append("    if ").append(toSafeName(parameters.get(index).getName())).append(" != None:").append(StringTools.LINE_DELIMITER);
 				body.append("        ").append("parameters_array[").append(index).append("] = ").append(toSafeName(parameters.get(index).getName()))
 						.append(StringTools.LINE_DELIMITER);
 			}

 			body.append("    ").append(EnvironmentModule.getWrappedVariableName(environment)).append(".preMethodCallback(\"").append(methodId)
 					.append("\", parameters_array)").append(StringTools.LINE_DELIMITER);

 		} else {
 			body.append("    ").append(EnvironmentModule.getWrappedVariableName(environment)).append(".preMethodCallback(\"").append(methodId).append("\"")
 					.append(parameters.isEmpty() ? "" : ", ").append(buildParameterList(parameters)).append(")").append(StringTools.LINE_DELIMITER);
 		}

 		body.append("    ").append(RESULT_NAME).append(" = ").append(classIdentifier).append(".").append(method.getName()).append("(")
 				.append(buildParameterList(parameters)).append(")").append(StringTools.LINE_DELIMITER);
 		body.append("    ").append(EnvironmentModule.getWrappedVariableName(environment)).append(".postMethodCallback(\"").append(methodId).append("\"")
 				.append(", ").append(RESULT_NAME).append(")").append(StringTools.LINE_DELIMITER);
 		body.append("    return ").append(RESULT_NAME).append(StringTools.LINE_DELIMITER);

 		return body.toString();
 	}

 	private static String indent(String code, String indentation) {
 		if (code.isEmpty())
 			return code;

 		return indentation + code.replaceAll("\n", "\n" + indentation).trim() + "\n";
 	}

 	@Override
 	public String getSaveVariableName(final String variableName) {
 		return PythonHelper.getSaveName(variableName);
 	}

 	@Override
 	public String classInstantiation(final Class<?> clazz, final String[] parameters) {
 		final StringBuilder code = new StringBuilder();
 		code.append(clazz.getCanonicalName());
 		code.append('(');

 		if (parameters != null) {
 			for (final String parameter : parameters) {
 				code.append(parameter);
 				code.append(", ");
 			}
 			if (parameters.length > 0)
 				code.delete(code.length() - 2, code.length());
 		}

 		code.append(')');

 		return code.toString();
 	}

 	public boolean isValidMethodName(final String methodName) {
 		return PythonHelper.isSaveName(methodName) && !RESERVED_KEYWORDS.contains(methodName);
 	}

 	@Override
 	protected String getNullString() {
 		return "None";
 	}

 	@Override
 	protected String getTrueString() {
 		return "True";
 	}

 	@Override
 	protected String getFalseString() {
 		return "False";
 	}

 	@Override
 	protected String getSingleLineCommentToken() {
 		return "# ";
 	}

 	@Override
 	protected String getMultiLineCommentStartToken() {
 		return "\"\"\"";
 	}

 	@Override
 	protected String getMultiLineCommentEndToken() {
 		return getMultiLineCommentStartToken();
 	}

 	@Override
 	protected Object getLanguageIdentifier() {
 		return "Python";
 	}

 	/**
 	 * Create wrapper code for Pep302 import statements.
 	 *
 	 * @param environment
 	 *            script environment instance
 	 * @param instance
 	 *            instance to wrap
 	 * @param identifier
 	 *            instance identifier to be used
 	 * @return wrapper code to be loaded by python
 	 */
 	public String createPep302WrapperCode(EnvironmentModule environment, Object instance, String identifier) {
 		return createWrapper(environment, instance, identifier, false, environment.getScriptEngine());
 	}

 	/**
 	 * Create wrapper code to convert all array parameters to actual Java arrays.
 	 *
 	 * @param parameters
 	 *            List of parameters to create array conversion for.
 	 * @return Wrapper code for performing array conversion.
 	 */
 	protected static String buildArrayConversions(List<Parameter> parameters) {
 		return parameters.stream().map(PythonCodeFactory::buildArrayConversion).collect(Collectors.joining(StringTools.LINE_DELIMITER));
 	}

 	/**
 	 * Create wrapper code to convert an array parameter to actual Java array.
 	 *
 	 * Generated code will have the following look: {@code
 	 * 	try:
 	 * 		tmp = gateway.new_array([array type], len([value to be converted]))
 	 *      for index, value in enumerate([value to be converted]):
 	 *          tmp[index] = value
 	 *      [value to be converted] = tmp
 	 *  except NameError:
 	 *      pass
 	 *  }
 	 *
 	 * @param parameter
 	 *            Parameter to create conversion code for.
 	 * @return Wrapper code for performing array conversion.
 	 */
 	protected static String buildArrayConversion(Parameter parameter) {
 		final StringBuilder builder = new StringBuilder();
 		if (parameter.getClazz().isArray()) {
 			final String arrayType = getPythonClassIdentifier(parameter.getClazz().getComponentType());
 			final String variableName = toSafeNameStatic(parameter.getName());
 			builder.append(String.format("if %s is not None:", variableName)).append(StringTools.LINE_DELIMITER);
 			builder.append("    try:").append(StringTools.LINE_DELIMITER);
 			builder.append(String.format("        tmp = gateway.new_array(%s, len(%s))", arrayType, variableName)).append(StringTools.LINE_DELIMITER);
 			builder.append(String.format("        for index, value in enumerate(%s):", variableName)).append(StringTools.LINE_DELIMITER);
 			builder.append("            tmp[index] = value").append(StringTools.LINE_DELIMITER);
 			builder.append(String.format("        %s =  tmp", variableName)).append(StringTools.LINE_DELIMITER);
 			builder.append("    except NameError:").append(StringTools.LINE_DELIMITER);
 			builder.append("        pass").append(StringTools.LINE_DELIMITER);
 		}
 		return builder.toString();
 	}

 	/**
 	 * List of Java primitive types as they need to be handled differently from normal classes when getting their py4j representation.
 	 *
 	 * bytes are handled differently as Python has native bytearray type.
 	 */
 	private static final List<Class<?>> PRIMITIVES = Arrays.asList(short.class, int.class, long.class, float.class, double.class, boolean.class, char.class);

 	/**
 	 * Returns the Python (py4j) identifier for the given class.
 	 *
 	 * @param cls
 	 *            Class to get py4j identifier for.
 	 * @return py4j class identifier.
 	 */
 	protected static String getPythonClassIdentifier(Class<?> cls) {
 		if (PRIMITIVES.contains(cls)) {
 			return String.format("gateway.jvm.%s", cls.getName());
 		} else {
 			return cls.getName();
 		}
 	}
 }
	/*******************************************************************************
	* Copyright (c) 2013, 2016 Atos and others.
	* All rights reserved. This program and the accompanying materials
	* are made available under the terms of the Eclipse Public License v2.0
	* which accompanies this distribution, and is available at
	* https://www.eclipse.org/legal/epl-2.0/
	*
	* Contributors:
	* Arthur Daussy - initial implementation
	* Christian Pontesegger - simplified to use base class
	*******************************************************************************/
	package org.eclipse.ease.lang.python;

	import java.lang.reflect.Field;
	import java.lang.reflect.Method;
	import java.util.ArrayList;
	import java.util.Arrays;
	import java.util.List;
	import java.util.stream.Collectors;

	import org.eclipse.ease.AbstractCodeFactory;
	import org.eclipse.ease.Logger;
	import org.eclipse.ease.modules.EnvironmentModule;
	import org.eclipse.ease.modules.IEnvironment;
	import org.eclipse.ease.modules.ModuleHelper;
	import org.eclipse.ease.tools.StringTools;

	public class PythonCodeFactory extends AbstractCodeFactory {

	public static List<String> RESERVED_KEYWORDS = new ArrayList<>();

	static {
	RESERVED_KEYWORDS.add("and");
	RESERVED_KEYWORDS.add("as");
	RESERVED_KEYWORDS.add("assert");
	RESERVED_KEYWORDS.add("break");
	RESERVED_KEYWORDS.add("class");
	RESERVED_KEYWORDS.add("continue");
	RESERVED_KEYWORDS.add("def");
	RESERVED_KEYWORDS.add("del");
	RESERVED_KEYWORDS.add("elif");
	RESERVED_KEYWORDS.add("else");
	RESERVED_KEYWORDS.add("except");
	RESERVED_KEYWORDS.add("exec");
	RESERVED_KEYWORDS.add("finally");
	RESERVED_KEYWORDS.add("for");
	RESERVED_KEYWORDS.add("from");
	RESERVED_KEYWORDS.add("global");
	RESERVED_KEYWORDS.add("if");
	RESERVED_KEYWORDS.add("import");
	RESERVED_KEYWORDS.add("in");
	RESERVED_KEYWORDS.add("is");
	RESERVED_KEYWORDS.add("lambda");
	RESERVED_KEYWORDS.add("not");
	RESERVED_KEYWORDS.add("or");
	RESERVED_KEYWORDS.add("pass");
	RESERVED_KEYWORDS.add("print");
	RESERVED_KEYWORDS.add("raise");
	RESERVED_KEYWORDS.add("return");
	RESERVED_KEYWORDS.add("try");
	RESERVED_KEYWORDS.add("while");
	RESERVED_KEYWORDS.add("with");
	RESERVED_KEYWORDS.add("yield");

	// built in functions
	RESERVED_KEYWORDS.add("__import__");
	RESERVED_KEYWORDS.add("abs");
	RESERVED_KEYWORDS.add("all");
	RESERVED_KEYWORDS.add("any");
	RESERVED_KEYWORDS.add("ascii");
	RESERVED_KEYWORDS.add("bin");
	RESERVED_KEYWORDS.add("bool");
	RESERVED_KEYWORDS.add("bytearray");
	RESERVED_KEYWORDS.add("bytes");
	RESERVED_KEYWORDS.add("callable");
	RESERVED_KEYWORDS.add("chr");
	RESERVED_KEYWORDS.add("classmethod");
	RESERVED_KEYWORDS.add("compile");
	RESERVED_KEYWORDS.add("complex");
	RESERVED_KEYWORDS.add("delattr");
	RESERVED_KEYWORDS.add("dict");
	RESERVED_KEYWORDS.add("dir");
	RESERVED_KEYWORDS.add("divmod");
	RESERVED_KEYWORDS.add("enumerate");
	RESERVED_KEYWORDS.add("eval");
	RESERVED_KEYWORDS.add("exec");
	RESERVED_KEYWORDS.add("filter");
	RESERVED_KEYWORDS.add("float");
	RESERVED_KEYWORDS.add("format");
	RESERVED_KEYWORDS.add("frozenset");
	RESERVED_KEYWORDS.add("getattr");
	RESERVED_KEYWORDS.add("globals");
	RESERVED_KEYWORDS.add("hasattr");
	RESERVED_KEYWORDS.add("hash");
	RESERVED_KEYWORDS.add("help");
	RESERVED_KEYWORDS.add("hex");
	RESERVED_KEYWORDS.add("id");
	RESERVED_KEYWORDS.add("input");
	RESERVED_KEYWORDS.add("int");
	RESERVED_KEYWORDS.add("isinstance");
	RESERVED_KEYWORDS.add("issubclass");
	RESERVED_KEYWORDS.add("iter");
	RESERVED_KEYWORDS.add("len");
	RESERVED_KEYWORDS.add("list");
	RESERVED_KEYWORDS.add("locals");
	RESERVED_KEYWORDS.add("map");
	RESERVED_KEYWORDS.add("max");
	RESERVED_KEYWORDS.add("memoryview");
	RESERVED_KEYWORDS.add("min");
	RESERVED_KEYWORDS.add("next");
	RESERVED_KEYWORDS.add("object");
	RESERVED_KEYWORDS.add("oct");
	RESERVED_KEYWORDS.add("open");
	RESERVED_KEYWORDS.add("ord");
	RESERVED_KEYWORDS.add("pow");
	RESERVED_KEYWORDS.add("print");
	RESERVED_KEYWORDS.add("property");
	RESERVED_KEYWORDS.add("range");
	RESERVED_KEYWORDS.add("repr");
	RESERVED_KEYWORDS.add("reversed");
	RESERVED_KEYWORDS.add("round");
	RESERVED_KEYWORDS.add("set");
	RESERVED_KEYWORDS.add("setattr");
	RESERVED_KEYWORDS.add("slice");
	RESERVED_KEYWORDS.add("sorted");
	RESERVED_KEYWORDS.add("staticmethod");
	RESERVED_KEYWORDS.add("str");
	RESERVED_KEYWORDS.add("sum");
	RESERVED_KEYWORDS.add("super");
	RESERVED_KEYWORDS.add("tuple");
	RESERVED_KEYWORDS.add("type");
	RESERVED_KEYWORDS.add("vars");
	RESERVED_KEYWORDS.add("zip");
	}

	private static String toSafeNameStatic(String name) {
	while (RESERVED_KEYWORDS.contains(name))
	name = name + "_";

	return name;
	}

	@Override
	protected String toSafeName(String name) {
	return toSafeNameStatic(name);
	}

	@Override
	protected String createFieldWrapper(IEnvironment environment, String identifier, Field field) {
	final StringBuilder pythonCode = new StringBuilder();

	pythonCode.append("import sys").append(StringTools.LINE_DELIMITER);

	pythonCode.append("if \"py4j\" in sys.modules:").append(StringTools.LINE_DELIMITER);
	pythonCode.append(" ");
	pythonCode.append(field.getName());
	pythonCode.append(" = py4j.java_gateway.get_field(");
	pythonCode.append(identifier);
	pythonCode.append(", \"");
	pythonCode.append(field.getName());
	pythonCode.append("\")");
	pythonCode.append(StringTools.LINE_DELIMITER);

	pythonCode.append("else:").append(StringTools.LINE_DELIMITER);
	pythonCode.append(" ");
	pythonCode.append(field.getName());
	pythonCode.append(" = ");
	pythonCode.append(identifier);
	pythonCode.append(".");
	pythonCode.append(field.getName());
	pythonCode.append(StringTools.LINE_DELIMITER);

	return pythonCode.toString();
	}

	@Override
	public String createFunctionWrapper(IEnvironment environment, final String moduleVariable, final Method method) {

	final StringBuilder pythonCode = new StringBuilder();

	// parse parameters
	final List<Parameter> parameters = ModuleHelper.getParameters(method);

	// build parameter string
	final StringBuilder methodSignature = new StringBuilder();
	final StringBuilder methodCall = new StringBuilder();

	for (final Parameter parameter : parameters) {
	methodSignature.append(", ").append(toSafeName(parameter.getName()));
	methodCall.append(", ").append(toSafeName(parameter.getName()));
	if (parameter.isOptional())
	methodSignature.append(" = ").append(getDefaultValue(parameter));
	}

	if (methodSignature.length() > 2) {
	methodSignature.delete(0, 2);
	methodCall.delete(0, 2);
	}

	final String body = buildMethodBody(parameters, method, moduleVariable, environment);

	// build function declarations
	for (final String name : getMethodNames(method)) {
	if (!isValidMethodName(name)) {
	Logger.error(Activator.PLUGIN_ID,
	"The method name \"" + name + "\" from the module \"" + moduleVariable + "\" can not be wrapped because it's name is reserved");

	} else if (!name.isEmpty()) {
	pythonCode.append("def ").append(name).append('(').append(methodSignature).append("):\n");
	pythonCode.append(indent(body, " "));
	pythonCode.append('\n');
	pythonCode.append(name).append(".__ease__ = True\n");
	pythonCode.append('\n');
	}
	}

	return pythonCode.toString();
	}

	private String buildMethodBody(List<Parameter> parameters, Method method, String classIdentifier, IEnvironment environment) {
	final StringBuilder body = new StringBuilder();

	final String methodId = ((EnvironmentModule) environment).registerMethod(method);

	// insert deprecation warnings
	if (ModuleHelper.isDeprecated(method))
	body.append("printError(\"" + method.getName() + "() is deprecated. Consider updating your code.\")").append(StringTools.LINE_DELIMITER);

	// Convert Lists to Java arrays
	body.append(buildArrayConversions(parameters)).append(StringTools.LINE_DELIMITER);

	// check for callbacks
	body.append("if not ").append(EnvironmentModule.getWrappedVariableName(environment)).append(".hasMethodCallback(\"").append(methodId).append("\"):")
	.append(StringTools.LINE_DELIMITER);

	// simple execution
	body.append(" return ").append(classIdentifier).append(".").append(method.getName()).append("(").append(buildParameterList(parameters)).append(")")
	.append(StringTools.LINE_DELIMITER);
	body.append(StringTools.LINE_DELIMITER);

	// execution with callbacks
	body.append("else:").append(StringTools.LINE_DELIMITER);
	if (environment.getScriptEngine().getDescription().getID().startsWith("org.eclipse.ease.lang.python.py4j")) {
	// special handling for Py4J as it cannot use java varargs parameters directly
	body.append(" ").append("parameters_array = gateway.new_array(gateway.jvm.Object, ").append(parameters.size()).append(")")
	.append(StringTools.LINE_DELIMITER);
	for (int index = 0; index < parameters.size(); index++) {
	// Py4J cannot execute
	// gateway.new_array(gateway.jvm.Object, 1)[0] = None
	// as the default value for array elements is null anyway, we simply do not set those
	body.append(" if ").append(toSafeName(parameters.get(index).getName())).append(" != None:").append(StringTools.LINE_DELIMITER);
	body.append(" ").append("parameters_array[").append(index).append("] = ").append(toSafeName(parameters.get(index).getName()))
	.append(StringTools.LINE_DELIMITER);
	}

	body.append(" ").append(EnvironmentModule.getWrappedVariableName(environment)).append(".preMethodCallback(\"").append(methodId)
	.append("\", parameters_array)").append(StringTools.LINE_DELIMITER);

	} else {
	body.append(" ").append(EnvironmentModule.getWrappedVariableName(environment)).append(".preMethodCallback(\"").append(methodId).append("\"")
	.append(parameters.isEmpty() ? "" : ", ").append(buildParameterList(parameters)).append(")").append(StringTools.LINE_DELIMITER);
	}

	body.append(" ").append(RESULT_NAME).append(" = ").append(classIdentifier).append(".").append(method.getName()).append("(")
	.append(buildParameterList(parameters)).append(")").append(StringTools.LINE_DELIMITER);
	body.append(" ").append(EnvironmentModule.getWrappedVariableName(environment)).append(".postMethodCallback(\"").append(methodId).append("\"")
	.append(", ").append(RESULT_NAME).append(")").append(StringTools.LINE_DELIMITER);
	body.append(" return ").append(RESULT_NAME).append(StringTools.LINE_DELIMITER);

	return body.toString();
	}

	private static String indent(String code, String indentation) {
	if (code.isEmpty())
	return code;

	return indentation + code.replaceAll("\n", "\n" + indentation).trim() + "\n";
	}

	@Override
	public String getSaveVariableName(final String variableName) {
	return PythonHelper.getSaveName(variableName);
	}

	@Override
	public String classInstantiation(final Class<?> clazz, final String[] parameters) {
	final StringBuilder code = new StringBuilder();
	code.append(clazz.getCanonicalName());
	code.append('(');

	if (parameters != null) {
	for (final String parameter : parameters) {
	code.append(parameter);
	code.append(", ");
	}
	if (parameters.length > 0)
	code.delete(code.length() - 2, code.length());
	}

	code.append(')');

	return code.toString();
	}

	public boolean isValidMethodName(final String methodName) {
	return PythonHelper.isSaveName(methodName) && !RESERVED_KEYWORDS.contains(methodName);
	}

	@Override
	protected String getNullString() {
	return "None";
	}

	@Override
	protected String getTrueString() {
	return "True";
	}

	@Override
	protected String getFalseString() {
	return "False";
	}

	@Override
	protected String getSingleLineCommentToken() {
	return "# ";
	}

	@Override
	protected String getMultiLineCommentStartToken() {
	return "\"\"\"";
	}

	@Override
	protected String getMultiLineCommentEndToken() {
	return getMultiLineCommentStartToken();
	}

	@Override
	protected Object getLanguageIdentifier() {
	return "Python";
	}

	/**
	* Create wrapper code for Pep302 import statements.
	*
	* @param environment
	* script environment instance
	* @param instance
	* instance to wrap
	* @param identifier
	* instance identifier to be used
	* @return wrapper code to be loaded by python
	*/
	public String createPep302WrapperCode(EnvironmentModule environment, Object instance, String identifier) {
	return createWrapper(environment, instance, identifier, false, environment.getScriptEngine());
	}

	/**
	* Create wrapper code to convert all array parameters to actual Java arrays.
	*
	* @param parameters
	* List of parameters to create array conversion for.
	* @return Wrapper code for performing array conversion.
	*/
	protected static String buildArrayConversions(List<Parameter> parameters) {
	return parameters.stream().map(PythonCodeFactory::buildArrayConversion).collect(Collectors.joining(StringTools.LINE_DELIMITER));
	}

	/**
	* Create wrapper code to convert an array parameter to actual Java array.
	*
	* Generated code will have the following look: {@code
	* try:
	* tmp = gateway.new_array([array type], len([value to be converted]))
	* for index, value in enumerate([value to be converted]):
	* tmp[index] = value
	* [value to be converted] = tmp
	* except NameError:
	* pass
	* }
	*
	* @param parameter
	* Parameter to create conversion code for.
	* @return Wrapper code for performing array conversion.
	*/
	protected static String buildArrayConversion(Parameter parameter) {
	final StringBuilder builder = new StringBuilder();
	if (parameter.getClazz().isArray()) {
	final String arrayType = getPythonClassIdentifier(parameter.getClazz().getComponentType());
	final String variableName = toSafeNameStatic(parameter.getName());
	builder.append(String.format("if %s is not None:", variableName)).append(StringTools.LINE_DELIMITER);
	builder.append(" try:").append(StringTools.LINE_DELIMITER);
	builder.append(String.format(" tmp = gateway.new_array(%s, len(%s))", arrayType, variableName)).append(StringTools.LINE_DELIMITER);
	builder.append(String.format(" for index, value in enumerate(%s):", variableName)).append(StringTools.LINE_DELIMITER);
	builder.append(" tmp[index] = value").append(StringTools.LINE_DELIMITER);
	builder.append(String.format(" %s = tmp", variableName)).append(StringTools.LINE_DELIMITER);
	builder.append(" except NameError:").append(StringTools.LINE_DELIMITER);
	builder.append(" pass").append(StringTools.LINE_DELIMITER);
	}
	return builder.toString();
	}

	/**
	* List of Java primitive types as they need to be handled differently from normal classes when getting their py4j representation.
	*
	* bytes are handled differently as Python has native bytearray type.
	*/
	private static final List<Class<?>> PRIMITIVES = Arrays.asList(short.class, int.class, long.class, float.class, double.class, boolean.class, char.class);

	/**
	* Returns the Python (py4j) identifier for the given class.
	*
	* @param cls
	* Class to get py4j identifier for.
	* @return py4j class identifier.
	*/
	protected static String getPythonClassIdentifier(Class<?> cls) {
	if (PRIMITIVES.contains(cls)) {
	return String.format("gateway.jvm.%s", cls.getName());
	} else {
	return cls.getName();
	}
	}
	}