private void runJava(PrintStream out, PrintStream err) {
Binding.out = out;
Binding.err = err;
Binding.ctx = bundle.getBundleContext();
try {
Callable<?> callable =
javacService.compileJavaSnippet(code, classLoaderContext, err).orElse(ERROR);
if (callable != ERROR) {
Object result = callable.call();
if (result != null) {
out.println(result);
}
code.commit();
} else {
code.abort();
}
} catch (Throwable e) {
code.abort();
e.printStackTrace(err);
}
}
@Override
public void execute(String line, PrintStream out, PrintStream err) {
Objects.requireNonNull(classLoaderContext, "Did not set ClassLoaderCapabilities");
CommandInvocation invocation = javaArgs.parse(line, JAVA_OPTIONS.separatorCode(' '));
if (invocation.hasOption(RESET_CODE_ARG)) {
code.resetCode();
}
if (invocation.hasOption(RESET_ALL_ARG)) {
code.resetAll();
}
String codeToRun = invocation.getUnprocessedInput();
@Nullable String className;
if (invocation.hasOption(CLASS_ARG) && (className = extractClassName(codeToRun, err)) != null) {
Optional<Class<Object>> javaClass =
javacService.compileJavaClass(classLoaderContext, className, codeToRun, err);
javaClass.ifPresent(out::println);
} else {
breakupJavaLines(codeToRun);
boolean show = invocation.hasOption(SHOW_ARG);
if (show) {
out.println(javacService.getJavaSnippetClass(code));
if (!codeToRun.isEmpty()) {
// add new lines between the code and its result
out.println();
}
}
// run the current code if some input was given, or in any case when no show option
if (!codeToRun.isEmpty() || !show) {
runJava(out, err);
}
}
}
@Override
public OutputStream pipe(String command, PrintStream out, PrintStream err) {
CommandInvocation invocation = javaArgs.parse(command, JAVA_OPTIONS.separatorCode(' '));
Matcher identifierMatcher = lambdaIdentifierRegex.matcher(invocation.getUnprocessedInput());
if (identifierMatcher.matches()) {
String lambdaArgIdentifier = identifierMatcher.group("id");
String lambdaBody = identifierMatcher.group("body").trim();
if (lambdaBody.endsWith(";")) {
lambdaBody = lambdaBody.substring(0, lambdaBody.length() - 1);
}
String lineConsumerCode =
"return (java.util.function.Function<String, ?>)"
+ "(("
+ lambdaArgIdentifier.trim()
+ ") -> "
+ lambdaBody
+ ")";
JavaCode functionCode = new JavaCode(code);
functionCode.addLine(lineConsumerCode);
Optional<Callable<?>> callable =
javacService.compileJavaSnippet(functionCode, classLoaderContext, err);
if (callable.isPresent()) {
try {
Function<String, ?> callback = (Function<String, ?>) callable.get().call();
return new LineOutputStream(
line -> {
@Nullable Object output = callback.apply(line);
if (output != null) {
out.println(output);
}
},
out);
} catch (Exception e) {
err.println(e);
}
}
}
throw new RuntimeException(
"When used in a pipeline, the Java snippet must be in the form of a "
+ "lambda of type Function<String, ?> that takes one text line of the input at a time.\n"
+ "Example: ... | java line -> line.contains(\"text\") ? line : null");
}
public ClassLoaderContext getClassLoaderContext() {
return javacService.getAugmentedClassLoaderContext(classLoaderContext);
}
public class JavaCommand implements Command, StreamingCommand {
private static final String JAVA_ID_REGEX =
"([a-zA-Z_$][a-zA-Z\\d_$]*\\.)*[a-zA-Z_$][a-zA-Z\\d_$]*";
static final String RESET_CODE_ARG = "-r";
static final String RESET_CODE_LONG_ARG = "--reset";
static final String RESET_ALL_ARG = "-t";
static final String RESET_ALL_LONG_ARG = "--reset-all";
static final String SHOW_ARG = "-s";
static final String SHOW_LONG_ARG = "--show";
static final String CLASS_ARG = "-c";
static final String CLASS_LONG_ARG = "--class-define";
private static final CommandHelper.CommandBreakupOptions JAVA_OPTIONS =
CommandHelper.CommandBreakupOptions.create().includeQuotes(true);
private Bundle bundle;
private final JavacService javacService = JavacService.createDefault();
private final JavaCode code;
private final Pattern lambdaIdentifierRegex =
Pattern.compile(
"\\s*(\\()?\\s*(?<id>" + JAVA_ID_REGEX + ")\\s*(\\))?\\s*->(?<body>.+)", Pattern.DOTALL);
private ClassLoaderCapabilities classLoaderContext;
private final ArgsSpec javaArgs =
ArgsSpec.builder()
.accepts(RESET_CODE_ARG, RESET_CODE_LONG_ARG)
.end()
.accepts(RESET_ALL_ARG, RESET_ALL_LONG_ARG)
.end()
.accepts(SHOW_ARG, SHOW_LONG_ARG)
.end()
.accepts(CLASS_ARG, CLASS_LONG_ARG)
.end()
.build();
@SuppressWarnings("ConstantConditions")
private static final Callable<?> ERROR = () -> null;
public JavaCommand() {
this.code = new JavaCode(() -> Optional.ofNullable(getClassLoaderContext()));
}
public ClassLoaderContext getClassLoaderContext() {
return javacService.getAugmentedClassLoaderContext(classLoaderContext);
}
public void setClassLoaderContext(ClassLoaderCapabilities classLoaderContext) {
this.classLoaderContext = classLoaderContext;
}
public void activate(BundleContext context) {
this.bundle = context.getBundle();
}
public void deactivate(BundleContext context) {
this.bundle = null;
}
@Override
public String getName() {
return "java";
}
@Override
public String getUsage() {
return "java [-r | -s | -t | <java snippet>] | " + "[-c <class definition>]";
}
@Override
public String getShortDescription() {
return "Run Java code statements.\n"
+ "\nAll statements entered previously, except return statements, are executed each time "
+ "a new statement is entered.\n"
+ "Previous statements can be forgotten with the -r (reset) option.\n"
+ "Permanent variables can be created by adding them to the 'binding' Map, whose contents\n"
+ "get expanded into local variables on execution."
+ "\n\n"
+ "The java command accepts the following flags:\n"
+ " \n"
+ " * "
+ RESET_CODE_ARG
+ ", "
+ RESET_CODE_LONG_ARG
+ ":\n"
+ " reset the current code statement buffer.\n"
+ " * "
+ RESET_ALL_ARG
+ ", "
+ RESET_ALL_LONG_ARG
+ ":\n"
+ " reset the current code statement buffer and imports.\n"
+ " * "
+ SHOW_ARG
+ ", "
+ SHOW_LONG_ARG
+ ":\n"
+ " show the current statement buffer.\n"
+ " * "
+ CLASS_ARG
+ ", "
+ CLASS_LONG_ARG
+ ":\n"
+ " define a Java class.\n"
+ "\n"
+ "Simple example:\n\n"
+ ">> java return 2 + 2\n"
+ "< 4\n\n"
+ "Binding example:\n\n"
+ ">> java binding.put(\"var\", 10);\n"
+ ">> java -r return var + 10; // var is still present even after using the -r option\n"
+ "< 20\n\n"
+ "Multi-line example to define a separate class:\n\n"
+ ">> :{\n"
+ "java -c class Person {\n"
+ " String name;\n"
+ " int age;\n"
+ " Person(String name, int age) {\n"
+ " this.name = name;\n"
+ " this.age = age;\n"
+ " }\n"
+ " public String toString() { return \"Person(\" + name + \",\" + age + \")\"; }"
+ "}\n"
+ ":}\n"
+ "< class Person\n"
+ ">> java return new Person(\"Mary\", 24);\n"
+ "< Person(Mary, 24)\n\n"
+ "When run through pipes, the Java snippet should be a Function<String, ?> that takes \n"
+ "each input line as an argument, returning something to be printed (or null).\n"
+ "Example:\n"
+ ">> some_command | java line -> line.contains(\"text\") ? line : null";
}
JavaCode getAutocompleContext() {
return code;
}
@Override
public OutputStream pipe(String command, PrintStream out, PrintStream err) {
CommandInvocation invocation = javaArgs.parse(command, JAVA_OPTIONS.separatorCode(' '));
Matcher identifierMatcher = lambdaIdentifierRegex.matcher(invocation.getUnprocessedInput());
if (identifierMatcher.matches()) {
String lambdaArgIdentifier = identifierMatcher.group("id");
String lambdaBody = identifierMatcher.group("body").trim();
if (lambdaBody.endsWith(";")) {
lambdaBody = lambdaBody.substring(0, lambdaBody.length() - 1);
}
String lineConsumerCode =
"return (java.util.function.Function<String, ?>)"
+ "(("
+ lambdaArgIdentifier.trim()
+ ") -> "
+ lambdaBody
+ ")";
JavaCode functionCode = new JavaCode(code);
functionCode.addLine(lineConsumerCode);
Optional<Callable<?>> callable =
javacService.compileJavaSnippet(functionCode, classLoaderContext, err);
if (callable.isPresent()) {
try {
Function<String, ?> callback = (Function<String, ?>) callable.get().call();
return new LineOutputStream(
line -> {
@Nullable Object output = callback.apply(line);
if (output != null) {
out.println(output);
}
},
out);
} catch (Exception e) {
err.println(e);
}
}
}
throw new RuntimeException(
"When used in a pipeline, the Java snippet must be in the form of a "
+ "lambda of type Function<String, ?> that takes one text line of the input at a time.\n"
+ "Example: ... | java line -> line.contains(\"text\") ? line : null");
}
@Override
public void execute(String line, PrintStream out, PrintStream err) {
Objects.requireNonNull(classLoaderContext, "Did not set ClassLoaderCapabilities");
CommandInvocation invocation = javaArgs.parse(line, JAVA_OPTIONS.separatorCode(' '));
if (invocation.hasOption(RESET_CODE_ARG)) {
code.resetCode();
}
if (invocation.hasOption(RESET_ALL_ARG)) {
code.resetAll();
}
String codeToRun = invocation.getUnprocessedInput();
@Nullable String className;
if (invocation.hasOption(CLASS_ARG) && (className = extractClassName(codeToRun, err)) != null) {
Optional<Class<Object>> javaClass =
javacService.compileJavaClass(classLoaderContext, className, codeToRun, err);
javaClass.ifPresent(out::println);
} else {
breakupJavaLines(codeToRun);
boolean show = invocation.hasOption(SHOW_ARG);
if (show) {
out.println(javacService.getJavaSnippetClass(code));
if (!codeToRun.isEmpty()) {
// add new lines between the code and its result
out.println();
}
}
// run the current code if some input was given, or in any case when no show option
if (!codeToRun.isEmpty() || !show) {
runJava(out, err);
}
}
}
@Nullable
private static String extractClassName(String code, PrintStream err) {
InputStream inputStream = new ByteArrayInputStream(code.getBytes(StandardCharsets.UTF_8));
try {
CompilationUnit compilationUnit = JavaParser.parse(inputStream);
List<TypeDeclaration> types = compilationUnit.getTypes();
if (types.size() == 1) {
String simpleType = types.get(0).getName();
return Optional.ofNullable(compilationUnit.getPackage())
.map(PackageDeclaration::getPackageName)
.map(it -> it + "." + simpleType)
.orElse(simpleType);
} else if (types.size() == 0) {
err.println("No class definition found");
} else {
err.println("Too many class definitions found. Only one class can be defined at a time.");
}
} catch (ParseException e) {
// ignore error, let the compiler provide an error message
return "Err";
}
return null;
}
private void runJava(PrintStream out, PrintStream err) {
Binding.out = out;
Binding.err = err;
Binding.ctx = bundle.getBundleContext();
try {
Callable<?> callable =
javacService.compileJavaSnippet(code, classLoaderContext, err).orElse(ERROR);
if (callable != ERROR) {
Object result = callable.call();
if (result != null) {
out.println(result);
}
code.commit();
} else {
code.abort();
}
} catch (Throwable e) {
code.abort();
e.printStackTrace(err);
}
}
private void breakupJavaLines(String input) {
CommandHelper.breakupArguments(
input,
(javaLine) -> {
javaLine = javaLine.trim();
if (!javaLine.isEmpty() && !javaLine.startsWith("//")) {
code.addLine(javaLine);
}
return true;
},
JAVA_OPTIONS.separatorCode(';'));
}
}