Java example source code file (RMIGenerator.java)
The RMIGenerator.java Java example source code
/*
* Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
/*****************************************************************************/
/* Copyright (c) IBM Corporation 1998 */
/* */
/* (C) Copyright IBM Corp. 1998 */
/* */
/*****************************************************************************/
package sun.rmi.rmic;
import java.io.File;
import java.io.FileOutputStream;
import java.io.OutputStreamWriter;
import java.io.IOException;
import java.util.Enumeration;
import java.util.Hashtable;
import java.util.Vector;
import sun.tools.java.Type;
import sun.tools.java.Identifier;
import sun.tools.java.ClassDefinition;
import sun.tools.java.ClassDeclaration;
import sun.tools.java.ClassNotFound;
import sun.tools.java.ClassFile;
import sun.tools.java.MemberDefinition;
import com.sun.corba.se.impl.util.Utility;
/**
* A Generator object will generate the Java source code of the stub
* and skeleton classes for an RMI remote implementation class, using
* a particular stub protocol version.
*
* WARNING: The contents of this source file are not part of any
* supported API. Code that depends on them does so at its own risk:
* they are subject to change or removal without notice.
*
* @author Peter Jones, Bryan Atsatt
*/
public class RMIGenerator implements RMIConstants, Generator {
private static final Hashtable<String, Integer> versionOptions = new Hashtable<>();
static {
versionOptions.put("-v1.1", new Integer(STUB_VERSION_1_1));
versionOptions.put("-vcompat", new Integer(STUB_VERSION_FAT));
versionOptions.put("-v1.2", new Integer(STUB_VERSION_1_2));
}
/**
* Default constructor for Main to use.
*/
public RMIGenerator() {
version = STUB_VERSION_1_2; // default is -v1.2 (see 4638155)
}
/**
* Examine and consume command line arguments.
* @param argv The command line arguments. Ignore null
* and unknown arguments. Set each consumed argument to null.
* @param error Report any errors using the main.error() methods.
* @return true if no errors, false otherwise.
*/
public boolean parseArgs(String argv[], Main main) {
String explicitVersion = null;
for (int i = 0; i < argv.length; i++) {
if (argv[i] != null) {
String arg = argv[i].toLowerCase();
if (versionOptions.containsKey(arg)) {
if (explicitVersion != null &&
!explicitVersion.equals(arg))
{
main.error("rmic.cannot.use.both",
explicitVersion, arg);
return false;
}
explicitVersion = arg;
version = versionOptions.get(arg);
argv[i] = null;
}
}
}
return true;
}
/**
* Generate the source files for the stub and/or skeleton classes
* needed by RMI for the given remote implementation class.
*
* @param env compiler environment
* @param cdef definition of remote implementation class
* to generate stubs and/or skeletons for
* @param destDir directory for the root of the package hierarchy
* for generated files
*/
public void generate(BatchEnvironment env, ClassDefinition cdef, File destDir) {
RemoteClass remoteClass = RemoteClass.forClass(env, cdef);
if (remoteClass == null) // exit if an error occurred
return;
RMIGenerator gen;
try {
gen = new RMIGenerator(env, cdef, destDir, remoteClass, version);
} catch (ClassNotFound e) {
env.error(0, "rmic.class.not.found", e.name);
return;
}
gen.generate();
}
private void generate() {
env.addGeneratedFile(stubFile);
try {
IndentingWriter out = new IndentingWriter(
new OutputStreamWriter(new FileOutputStream(stubFile)));
writeStub(out);
out.close();
if (env.verbose()) {
env.output(Main.getText("rmic.wrote", stubFile.getPath()));
}
env.parseFile(new ClassFile(stubFile));
} catch (IOException e) {
env.error(0, "cant.write", stubFile.toString());
return;
}
if (version == STUB_VERSION_1_1 ||
version == STUB_VERSION_FAT)
{
env.addGeneratedFile(skeletonFile);
try {
IndentingWriter out = new IndentingWriter(
new OutputStreamWriter(
new FileOutputStream(skeletonFile)));
writeSkeleton(out);
out.close();
if (env.verbose()) {
env.output(Main.getText("rmic.wrote",
skeletonFile.getPath()));
}
env.parseFile(new ClassFile(skeletonFile));
} catch (IOException e) {
env.error(0, "cant.write", stubFile.toString());
return;
}
} else {
/*
* For bugid 4135136: if skeleton files are not being generated
* for this compilation run, delete old skeleton source or class
* files for this remote implementation class that were
* (presumably) left over from previous runs, to avoid user
* confusion from extraneous or inconsistent generated files.
*/
File outputDir = Util.getOutputDirectoryFor(remoteClassName,destDir,env);
File skeletonClassFile = new File(outputDir,skeletonClassName.getName().toString() + ".class");
skeletonFile.delete(); // ignore failures (no big deal)
skeletonClassFile.delete();
}
}
/**
* Return the File object that should be used as the source file
* for the given Java class, using the supplied destination
* directory for the top of the package hierarchy.
*/
protected static File sourceFileForClass(Identifier className,
Identifier outputClassName,
File destDir,
BatchEnvironment env)
{
File packageDir = Util.getOutputDirectoryFor(className,destDir,env);
String outputName = Names.mangleClass(outputClassName).getName().toString();
// Is there any existing _Tie equivalent leftover from a
// previous invocation of rmic -iiop? Only do this once per
// class by looking for skeleton generation...
if (outputName.endsWith("_Skel")) {
String classNameStr = className.getName().toString();
File temp = new File(packageDir, Utility.tieName(classNameStr) + ".class");
if (temp.exists()) {
// Found a tie. Is IIOP generation also being done?
if (!env.getMain().iiopGeneration) {
// No, so write a warning...
env.error(0,"warn.rmic.tie.found",
classNameStr,
temp.getAbsolutePath());
}
}
}
String outputFileName = outputName + ".java";
return new File(packageDir, outputFileName);
}
/** rmic environment for this object */
private BatchEnvironment env;
/** the remote class that this instance is generating code for */
private RemoteClass remoteClass;
/** version of the stub protocol to use in code generation */
private int version;
/** remote methods for remote class, indexed by operation number */
private RemoteClass.Method[] remoteMethods;
/**
* Names for the remote class and the stub and skeleton classes
* to be generated for it.
*/
private Identifier remoteClassName;
private Identifier stubClassName;
private Identifier skeletonClassName;
private ClassDefinition cdef;
private File destDir;
private File stubFile;
private File skeletonFile;
/**
* Names to use for the java.lang.reflect.Method static fields
* corresponding to each remote method.
*/
private String[] methodFieldNames;
/** cached definition for certain exception classes in this environment */
private ClassDefinition defException;
private ClassDefinition defRemoteException;
private ClassDefinition defRuntimeException;
/**
* Create a new stub/skeleton Generator object for the given
* remote implementation class to generate code according to
* the given stub protocol version.
*/
private RMIGenerator(BatchEnvironment env, ClassDefinition cdef,
File destDir, RemoteClass remoteClass, int version)
throws ClassNotFound
{
this.destDir = destDir;
this.cdef = cdef;
this.env = env;
this.remoteClass = remoteClass;
this.version = version;
remoteMethods = remoteClass.getRemoteMethods();
remoteClassName = remoteClass.getName();
stubClassName = Names.stubFor(remoteClassName);
skeletonClassName = Names.skeletonFor(remoteClassName);
methodFieldNames = nameMethodFields(remoteMethods);
stubFile = sourceFileForClass(remoteClassName,stubClassName, destDir , env);
skeletonFile = sourceFileForClass(remoteClassName,skeletonClassName, destDir, env);
/*
* Initialize cached definitions for exception classes used
* in the generation process.
*/
defException =
env.getClassDeclaration(idJavaLangException).
getClassDefinition(env);
defRemoteException =
env.getClassDeclaration(idRemoteException).
getClassDefinition(env);
defRuntimeException =
env.getClassDeclaration(idJavaLangRuntimeException).
getClassDefinition(env);
}
/**
* Write the stub for the remote class to a stream.
*/
private void writeStub(IndentingWriter p) throws IOException {
/*
* Write boiler plate comment.
*/
p.pln("// Stub class generated by rmic, do not edit.");
p.pln("// Contents subject to change without notice.");
p.pln();
/*
* If remote implementation class was in a particular package,
* declare the stub class to be in the same package.
*/
if (remoteClassName.isQualified()) {
p.pln("package " + remoteClassName.getQualifier() + ";");
p.pln();
}
/*
* Declare the stub class; implement all remote interfaces.
*/
p.plnI("public final class " +
Names.mangleClass(stubClassName.getName()));
p.pln("extends " + idRemoteStub);
ClassDefinition[] remoteInterfaces = remoteClass.getRemoteInterfaces();
if (remoteInterfaces.length > 0) {
p.p("implements ");
for (int i = 0; i < remoteInterfaces.length; i++) {
if (i > 0)
p.p(", ");
p.p(remoteInterfaces[i].getName().toString());
}
p.pln();
}
p.pOlnI("{");
if (version == STUB_VERSION_1_1 ||
version == STUB_VERSION_FAT)
{
writeOperationsArray(p);
p.pln();
writeInterfaceHash(p);
p.pln();
}
if (version == STUB_VERSION_FAT ||
version == STUB_VERSION_1_2)
{
p.pln("private static final long serialVersionUID = " +
STUB_SERIAL_VERSION_UID + ";");
p.pln();
/*
* We only need to declare and initialize the static fields of
* Method objects for each remote method if there are any remote
* methods; otherwise, skip this code entirely, to avoid generating
* a try/catch block for a checked exception that cannot occur
* (see bugid 4125181).
*/
if (methodFieldNames.length > 0) {
if (version == STUB_VERSION_FAT) {
p.pln("private static boolean useNewInvoke;");
}
writeMethodFieldDeclarations(p);
p.pln();
/*
* Initialize java.lang.reflect.Method fields for each remote
* method in a static initializer.
*/
p.plnI("static {");
p.plnI("try {");
if (version == STUB_VERSION_FAT) {
/*
* Fat stubs must determine whether the API required for
* the JDK 1.2 stub protocol is supported in the current
* runtime, so that it can use it if supported. This is
* determined by using the Reflection API to test if the
* new invoke method on RemoteRef exists, and setting the
* static boolean "useNewInvoke" to true if it does, or
* to false if a NoSuchMethodException is thrown.
*/
p.plnI(idRemoteRef + ".class.getMethod(\"invoke\",");
p.plnI("new java.lang.Class[] {");
p.pln(idRemote + ".class,");
p.pln("java.lang.reflect.Method.class,");
p.pln("java.lang.Object[].class,");
p.pln("long.class");
p.pOln("});");
p.pO();
p.pln("useNewInvoke = true;");
}
writeMethodFieldInitializers(p);
p.pOlnI("} catch (java.lang.NoSuchMethodException e) {");
if (version == STUB_VERSION_FAT) {
p.pln("useNewInvoke = false;");
} else {
/*
* REMIND: By throwing an Error here, the application will
* get the NoSuchMethodError directly when the stub class
* is initialized. If we throw a RuntimeException
* instead, the application would get an
* ExceptionInInitializerError. Would that be more
* appropriate, and if so, which RuntimeException should
* be thrown?
*/
p.plnI("throw new java.lang.NoSuchMethodError(");
p.pln("\"stub class initialization failed\");");
p.pO();
}
p.pOln("}"); // end try/catch block
p.pOln("}"); // end static initializer
p.pln();
}
}
writeStubConstructors(p);
p.pln();
/*
* Write each stub method.
*/
if (remoteMethods.length > 0) {
p.pln("// methods from remote interfaces");
for (int i = 0; i < remoteMethods.length; ++i) {
p.pln();
writeStubMethod(p, i);
}
}
p.pOln("}"); // end stub class
}
/**
* Write the constructors for the stub class.
*/
private void writeStubConstructors(IndentingWriter p)
throws IOException
{
p.pln("// constructors");
/*
* Only stubs compatible with the JDK 1.1 stub protocol need
* a no-arg constructor; later versions use reflection to find
* the constructor that directly takes a RemoteRef argument.
*/
if (version == STUB_VERSION_1_1 ||
version == STUB_VERSION_FAT)
{
p.plnI("public " + Names.mangleClass(stubClassName.getName()) +
"() {");
p.pln("super();");
p.pOln("}");
}
p.plnI("public " + Names.mangleClass(stubClassName.getName()) +
"(" + idRemoteRef + " ref) {");
p.pln("super(ref);");
p.pOln("}");
}
/**
* Write the stub method for the remote method with the given "opnum".
*/
private void writeStubMethod(IndentingWriter p, int opnum)
throws IOException
{
RemoteClass.Method method = remoteMethods[opnum];
Identifier methodName = method.getName();
Type methodType = method.getType();
Type paramTypes[] = methodType.getArgumentTypes();
String paramNames[] = nameParameters(paramTypes);
Type returnType = methodType.getReturnType();
ClassDeclaration[] exceptions = method.getExceptions();
/*
* Declare stub method; throw exceptions declared in remote
* interface(s).
*/
p.pln("// implementation of " +
methodType.typeString(methodName.toString(), true, false));
p.p("public " + returnType + " " + methodName + "(");
for (int i = 0; i < paramTypes.length; i++) {
if (i > 0)
p.p(", ");
p.p(paramTypes[i] + " " + paramNames[i]);
}
p.plnI(")");
if (exceptions.length > 0) {
p.p("throws ");
for (int i = 0; i < exceptions.length; i++) {
if (i > 0)
p.p(", ");
p.p(exceptions[i].getName().toString());
}
p.pln();
}
p.pOlnI("{");
/*
* The RemoteRef.invoke methods throw Exception, but unless this
* stub method throws Exception as well, we must catch Exceptions
* thrown from the invocation. So we must catch Exception and
* rethrow something we can throw: UnexpectedException, which is a
* subclass of RemoteException. But for any subclasses of Exception
* that we can throw, like RemoteException, RuntimeException, and
* any of the exceptions declared by this stub method, we want them
* to pass through unharmed, so first we must catch any such
* exceptions and rethrow it directly.
*
* We have to be careful generating the rethrowing catch blocks
* here, because javac will flag an error if there are any
* unreachable catch blocks, i.e. if the catch of an exception class
* follows a previous catch of it or of one of its superclasses.
* The following method invocation takes care of these details.
*/
Vector<ClassDefinition> catchList = computeUniqueCatchList(exceptions);
/*
* If we need to catch any particular exceptions (i.e. this method
* does not declare java.lang.Exception), put the entire stub
* method in a try block.
*/
if (catchList.size() > 0) {
p.plnI("try {");
}
if (version == STUB_VERSION_FAT) {
p.plnI("if (useNewInvoke) {");
}
if (version == STUB_VERSION_FAT ||
version == STUB_VERSION_1_2)
{
if (!returnType.isType(TC_VOID)) {
p.p("Object $result = "); // REMIND: why $?
}
p.p("ref.invoke(this, " + methodFieldNames[opnum] + ", ");
if (paramTypes.length > 0) {
p.p("new java.lang.Object[] {");
for (int i = 0; i < paramTypes.length; i++) {
if (i > 0)
p.p(", ");
p.p(wrapArgumentCode(paramTypes[i], paramNames[i]));
}
p.p("}");
} else {
p.p("null");
}
p.pln(", " + method.getMethodHash() + "L);");
if (!returnType.isType(TC_VOID)) {
p.pln("return " +
unwrapArgumentCode(returnType, "$result") + ";");
}
}
if (version == STUB_VERSION_FAT) {
p.pOlnI("} else {");
}
if (version == STUB_VERSION_1_1 ||
version == STUB_VERSION_FAT)
{
p.pln(idRemoteCall + " call = ref.newCall((" + idRemoteObject +
") this, operations, " + opnum + ", interfaceHash);");
if (paramTypes.length > 0) {
p.plnI("try {");
p.pln("java.io.ObjectOutput out = call.getOutputStream();");
writeMarshalArguments(p, "out", paramTypes, paramNames);
p.pOlnI("} catch (java.io.IOException e) {");
p.pln("throw new " + idMarshalException +
"(\"error marshalling arguments\", e);");
p.pOln("}");
}
p.pln("ref.invoke(call);");
if (returnType.isType(TC_VOID)) {
p.pln("ref.done(call);");
} else {
p.pln(returnType + " $result;"); // REMIND: why $?
p.plnI("try {");
p.pln("java.io.ObjectInput in = call.getInputStream();");
boolean objectRead =
writeUnmarshalArgument(p, "in", returnType, "$result");
p.pln(";");
p.pOlnI("} catch (java.io.IOException e) {");
p.pln("throw new " + idUnmarshalException +
"(\"error unmarshalling return\", e);");
/*
* If any only if readObject has been invoked, we must catch
* ClassNotFoundException as well as IOException.
*/
if (objectRead) {
p.pOlnI("} catch (java.lang.ClassNotFoundException e) {");
p.pln("throw new " + idUnmarshalException +
"(\"error unmarshalling return\", e);");
}
p.pOlnI("} finally {");
p.pln("ref.done(call);");
p.pOln("}");
p.pln("return $result;");
}
}
if (version == STUB_VERSION_FAT) {
p.pOln("}"); // end if/else (useNewInvoke) block
}
/*
* If we need to catch any particular exceptions, finally write
* the catch blocks for them, rethrow any other Exceptions with an
* UnexpectedException, and end the try block.
*/
if (catchList.size() > 0) {
for (Enumeration<ClassDefinition> enumeration = catchList.elements();
enumeration.hasMoreElements();)
{
ClassDefinition def = enumeration.nextElement();
p.pOlnI("} catch (" + def.getName() + " e) {");
p.pln("throw e;");
}
p.pOlnI("} catch (java.lang.Exception e) {");
p.pln("throw new " + idUnexpectedException +
"(\"undeclared checked exception\", e);");
p.pOln("}"); // end try/catch block
}
p.pOln("}"); // end stub method
}
/**
* Compute the exceptions which need to be caught and rethrown in a
* stub method before wrapping Exceptions in UnexpectedExceptions,
* given the exceptions declared in the throws clause of the method.
* Returns a Vector containing ClassDefinition objects for each
* exception to catch. Each exception is guaranteed to be unique,
* i.e. not a subclass of any of the other exceptions in the Vector,
* so the catch blocks for these exceptions may be generated in any
* order relative to each other.
*
* RemoteException and RuntimeException are each automatically placed
* in the returned Vector (if none of their superclasses are already
* present), since those exceptions should always be directly rethrown
* by a stub method.
*
* The returned Vector will be empty if java.lang.Exception or one
* of its superclasses is in the throws clause of the method, indicating
* that no exceptions need to be caught.
*/
private Vector<ClassDefinition> computeUniqueCatchList(ClassDeclaration[] exceptions) {
Vector<ClassDefinition> uniqueList = new Vector<>(); // unique exceptions to catch
uniqueList.addElement(defRuntimeException);
uniqueList.addElement(defRemoteException);
/* For each exception declared by the stub method's throws clause: */
nextException:
for (int i = 0; i < exceptions.length; i++) {
ClassDeclaration decl = exceptions[i];
try {
if (defException.subClassOf(env, decl)) {
/*
* (If java.lang.Exception (or a superclass) was declared
* in the throws clause of this stub method, then we don't
* have to bother catching anything; clear the list and
* return.)
*/
uniqueList.clear();
break;
} else if (!defException.superClassOf(env, decl)) {
/*
* Ignore other Throwables that do not extend Exception,
* since they do not need to be caught anyway.
*/
continue;
}
/*
* Compare this exception against the current list of
* exceptions that need to be caught:
*/
for (int j = 0; j < uniqueList.size();) {
ClassDefinition def = uniqueList.elementAt(j);
if (def.superClassOf(env, decl)) {
/*
* If a superclass of this exception is already on
* the list to catch, then ignore and continue;
*/
continue nextException;
} else if (def.subClassOf(env, decl)) {
/*
* If a subclass of this exception is on the list
* to catch, then remove it.
*/
uniqueList.removeElementAt(j);
} else {
j++; // else continue comparing
}
}
/* This exception is unique: add it to the list to catch. */
uniqueList.addElement(decl.getClassDefinition(env));
} catch (ClassNotFound e) {
env.error(0, "class.not.found", e.name, decl.getName());
/*
* REMIND: We do not exit from this exceptional condition,
* generating questionable code and likely letting the
* compiler report a resulting error later.
*/
}
}
return uniqueList;
}
/**
* Write the skeleton for the remote class to a stream.
*/
private void writeSkeleton(IndentingWriter p) throws IOException {
if (version == STUB_VERSION_1_2) {
throw new Error("should not generate skeleton for version");
}
/*
* Write boiler plate comment.
*/
p.pln("// Skeleton class generated by rmic, do not edit.");
p.pln("// Contents subject to change without notice.");
p.pln();
/*
* If remote implementation class was in a particular package,
* declare the skeleton class to be in the same package.
*/
if (remoteClassName.isQualified()) {
p.pln("package " + remoteClassName.getQualifier() + ";");
p.pln();
}
/*
* Declare the skeleton class.
*/
p.plnI("public final class " +
Names.mangleClass(skeletonClassName.getName()));
p.pln("implements " + idSkeleton);
p.pOlnI("{");
writeOperationsArray(p);
p.pln();
writeInterfaceHash(p);
p.pln();
/*
* Define the getOperations() method.
*/
p.plnI("public " + idOperation + "[] getOperations() {");
p.pln("return (" + idOperation + "[]) operations.clone();");
p.pOln("}");
p.pln();
/*
* Define the dispatch() method.
*/
p.plnI("public void dispatch(" + idRemote + " obj, " +
idRemoteCall + " call, int opnum, long hash)");
p.pln("throws java.lang.Exception");
p.pOlnI("{");
if (version == STUB_VERSION_FAT) {
p.plnI("if (opnum < 0) {");
if (remoteMethods.length > 0) {
for (int opnum = 0; opnum < remoteMethods.length; opnum++) {
if (opnum > 0)
p.pO("} else ");
p.plnI("if (hash == " +
remoteMethods[opnum].getMethodHash() + "L) {");
p.pln("opnum = " + opnum + ";");
}
p.pOlnI("} else {");
}
/*
* Skeleton throws UnmarshalException if it does not recognize
* the method hash; this is what UnicastServerRef.dispatch()
* would do.
*/
p.pln("throw new " +
idUnmarshalException + "(\"invalid method hash\");");
if (remoteMethods.length > 0) {
p.pOln("}");
}
/*
* Ignore the validation of the interface hash if the
* operation number was negative, since it is really a
* method hash instead.
*/
p.pOlnI("} else {");
}
p.plnI("if (hash != interfaceHash)");
p.pln("throw new " +
idSkeletonMismatchException + "(\"interface hash mismatch\");");
p.pO();
if (version == STUB_VERSION_FAT) {
p.pOln("}"); // end if/else (opnum < 0) block
}
p.pln();
/*
* Cast remote object instance to our specific implementation class.
*/
p.pln(remoteClassName + " server = (" + remoteClassName + ") obj;");
/*
* Process call according to the operation number.
*/
p.plnI("switch (opnum) {");
for (int opnum = 0; opnum < remoteMethods.length; opnum++) {
writeSkeletonDispatchCase(p, opnum);
}
p.pOlnI("default:");
/*
* Skeleton throws UnmarshalException if it does not recognize
* the operation number; this is consistent with the case of an
* unrecognized method hash.
*/
p.pln("throw new " + idUnmarshalException +
"(\"invalid method number\");");
p.pOln("}"); // end switch statement
p.pOln("}"); // end dispatch() method
p.pOln("}"); // end skeleton class
}
/**
* Write the case block for the skeleton's dispatch method for
* the remote method with the given "opnum".
*/
private void writeSkeletonDispatchCase(IndentingWriter p, int opnum)
throws IOException
{
RemoteClass.Method method = remoteMethods[opnum];
Identifier methodName = method.getName();
Type methodType = method.getType();
Type paramTypes[] = methodType.getArgumentTypes();
String paramNames[] = nameParameters(paramTypes);
Type returnType = methodType.getReturnType();
p.pOlnI("case " + opnum + ": // " +
methodType.typeString(methodName.toString(), true, false));
/*
* Use nested block statement inside case to provide an independent
* namespace for local variables used to unmarshal parameters for
* this remote method.
*/
p.pOlnI("{");
if (paramTypes.length > 0) {
/*
* Declare local variables to hold arguments.
*/
for (int i = 0; i < paramTypes.length; i++) {
p.pln(paramTypes[i] + " " + paramNames[i] + ";");
}
/*
* Unmarshal arguments from call stream.
*/
p.plnI("try {");
p.pln("java.io.ObjectInput in = call.getInputStream();");
boolean objectsRead = writeUnmarshalArguments(p, "in",
paramTypes, paramNames);
p.pOlnI("} catch (java.io.IOException e) {");
p.pln("throw new " + idUnmarshalException +
"(\"error unmarshalling arguments\", e);");
/*
* If any only if readObject has been invoked, we must catch
* ClassNotFoundException as well as IOException.
*/
if (objectsRead) {
p.pOlnI("} catch (java.lang.ClassNotFoundException e) {");
p.pln("throw new " + idUnmarshalException +
"(\"error unmarshalling arguments\", e);");
}
p.pOlnI("} finally {");
p.pln("call.releaseInputStream();");
p.pOln("}");
} else {
p.pln("call.releaseInputStream();");
}
if (!returnType.isType(TC_VOID)) {
/*
* Declare variable to hold return type, if not void.
*/
p.p(returnType + " $result = "); // REMIND: why $?
}
/*
* Invoke the method on the server object.
*/
p.p("server." + methodName + "(");
for (int i = 0; i < paramNames.length; i++) {
if (i > 0)
p.p(", ");
p.p(paramNames[i]);
}
p.pln(");");
/*
* Always invoke getResultStream(true) on the call object to send
* the indication of a successful invocation to the caller. If
* the return type is not void, keep the result stream and marshal
* the return value.
*/
p.plnI("try {");
if (!returnType.isType(TC_VOID)) {
p.p("java.io.ObjectOutput out = ");
}
p.pln("call.getResultStream(true);");
if (!returnType.isType(TC_VOID)) {
writeMarshalArgument(p, "out", returnType, "$result");
p.pln(";");
}
p.pOlnI("} catch (java.io.IOException e) {");
p.pln("throw new " +
idMarshalException + "(\"error marshalling return\", e);");
p.pOln("}");
p.pln("break;"); // break from switch statement
p.pOlnI("}"); // end nested block statement
p.pln();
}
/**
* Write declaration and initializer for "operations" static array.
*/
private void writeOperationsArray(IndentingWriter p)
throws IOException
{
p.plnI("private static final " + idOperation + "[] operations = {");
for (int i = 0; i < remoteMethods.length; i++) {
if (i > 0)
p.pln(",");
p.p("new " + idOperation + "(\"" +
remoteMethods[i].getOperationString() + "\")");
}
p.pln();
p.pOln("};");
}
/**
* Write declaration and initializer for "interfaceHash" static field.
*/
private void writeInterfaceHash(IndentingWriter p)
throws IOException
{
p.pln("private static final long interfaceHash = " +
remoteClass.getInterfaceHash() + "L;");
}
/**
* Write declaration for java.lang.reflect.Method static fields
* corresponding to each remote method in a stub.
*/
private void writeMethodFieldDeclarations(IndentingWriter p)
throws IOException
{
for (int i = 0; i < methodFieldNames.length; i++) {
p.pln("private static java.lang.reflect.Method " +
methodFieldNames[i] + ";");
}
}
/**
* Write code to initialize the static fields for each method
* using the Java Reflection API.
*/
private void writeMethodFieldInitializers(IndentingWriter p)
throws IOException
{
for (int i = 0; i < methodFieldNames.length; i++) {
p.p(methodFieldNames[i] + " = ");
/*
* Here we look up the Method object in the arbitrary interface
* that we find in the RemoteClass.Method object.
* REMIND: Is this arbitrary choice OK?
* REMIND: Should this access be part of RemoteClass.Method's
* abstraction?
*/
RemoteClass.Method method = remoteMethods[i];
MemberDefinition def = method.getMemberDefinition();
Identifier methodName = method.getName();
Type methodType = method.getType();
Type paramTypes[] = methodType.getArgumentTypes();
p.p(def.getClassDefinition().getName() + ".class.getMethod(\"" +
methodName + "\", new java.lang.Class[] {");
for (int j = 0; j < paramTypes.length; j++) {
if (j > 0)
p.p(", ");
p.p(paramTypes[j] + ".class");
}
p.pln("});");
}
}
/*
* Following are a series of static utility methods useful during
* the code generation process:
*/
/**
* Generate an array of names for fields that correspond to the given
* array of remote methods. Each name in the returned array is
* guaranteed to be unique.
*
* The name of a method is included in its corresponding field name
* to enhance readability of the generated code.
*/
private static String[] nameMethodFields(RemoteClass.Method[] methods) {
String[] names = new String[methods.length];
for (int i = 0; i < names.length; i++) {
names[i] = "$method_" + methods[i].getName() + "_" + i;
}
return names;
}
/**
* Generate an array of names for parameters corresponding to the
* given array of types for the parameters. Each name in the returned
* array is guaranteed to be unique.
*
* A representation of the type of a parameter is included in its
* corresponding field name to enhance the readability of the generated
* code.
*/
private static String[] nameParameters(Type[] types) {
String[] names = new String[types.length];
for (int i = 0; i < names.length; i++) {
names[i] = "$param_" +
generateNameFromType(types[i]) + "_" + (i + 1);
}
return names;
}
/**
* Generate a readable string representing the given type suitable
* for embedding within a Java identifier.
*/
private static String generateNameFromType(Type type) {
int typeCode = type.getTypeCode();
switch (typeCode) {
case TC_BOOLEAN:
case TC_BYTE:
case TC_CHAR:
case TC_SHORT:
case TC_INT:
case TC_LONG:
case TC_FLOAT:
case TC_DOUBLE:
return type.toString();
case TC_ARRAY:
return "arrayOf_" + generateNameFromType(type.getElementType());
case TC_CLASS:
return Names.mangleClass(type.getClassName().getName()).toString();
default:
throw new Error("unexpected type code: " + typeCode);
}
}
/**
* Write a snippet of Java code to marshal a value named "name" of
* type "type" to the java.io.ObjectOutput stream named "stream".
*
* Primitive types are marshalled with their corresponding methods
* in the java.io.DataOutput interface, and objects (including arrays)
* are marshalled using the writeObject method.
*/
private static void writeMarshalArgument(IndentingWriter p,
String streamName,
Type type, String name)
throws IOException
{
int typeCode = type.getTypeCode();
switch (typeCode) {
case TC_BOOLEAN:
p.p(streamName + ".writeBoolean(" + name + ")");
break;
case TC_BYTE:
p.p(streamName + ".writeByte(" + name + ")");
break;
case TC_CHAR:
p.p(streamName + ".writeChar(" + name + ")");
break;
case TC_SHORT:
p.p(streamName + ".writeShort(" + name + ")");
break;
case TC_INT:
p.p(streamName + ".writeInt(" + name + ")");
break;
case TC_LONG:
p.p(streamName + ".writeLong(" + name + ")");
break;
case TC_FLOAT:
p.p(streamName + ".writeFloat(" + name + ")");
break;
case TC_DOUBLE:
p.p(streamName + ".writeDouble(" + name + ")");
break;
case TC_ARRAY:
case TC_CLASS:
p.p(streamName + ".writeObject(" + name + ")");
break;
default:
throw new Error("unexpected type code: " + typeCode);
}
}
/**
* Write Java statements to marshal a series of values in order as
* named in the "names" array, with types as specified in the "types"
* array", to the java.io.ObjectOutput stream named "stream".
*/
private static void writeMarshalArguments(IndentingWriter p,
String streamName,
Type[] types, String[] names)
throws IOException
{
if (types.length != names.length) {
throw new Error("parameter type and name arrays different sizes");
}
for (int i = 0; i < types.length; i++) {
writeMarshalArgument(p, streamName, types[i], names[i]);
p.pln(";");
}
}
/**
* Write a snippet of Java code to unmarshal a value of type "type"
* from the java.io.ObjectInput stream named "stream" into a variable
* named "name" (if "name" is null, the value in unmarshalled and
* discarded).
*
* Primitive types are unmarshalled with their corresponding methods
* in the java.io.DataInput interface, and objects (including arrays)
* are unmarshalled using the readObject method.
*/
private static boolean writeUnmarshalArgument(IndentingWriter p,
String streamName,
Type type, String name)
throws IOException
{
boolean readObject = false;
if (name != null) {
p.p(name + " = ");
}
int typeCode = type.getTypeCode();
switch (type.getTypeCode()) {
case TC_BOOLEAN:
p.p(streamName + ".readBoolean()");
break;
case TC_BYTE:
p.p(streamName + ".readByte()");
break;
case TC_CHAR:
p.p(streamName + ".readChar()");
break;
case TC_SHORT:
p.p(streamName + ".readShort()");
break;
case TC_INT:
p.p(streamName + ".readInt()");
break;
case TC_LONG:
p.p(streamName + ".readLong()");
break;
case TC_FLOAT:
p.p(streamName + ".readFloat()");
break;
case TC_DOUBLE:
p.p(streamName + ".readDouble()");
break;
case TC_ARRAY:
case TC_CLASS:
p.p("(" + type + ") " + streamName + ".readObject()");
readObject = true;
break;
default:
throw new Error("unexpected type code: " + typeCode);
}
return readObject;
}
/**
* Write Java statements to unmarshal a series of values in order of
* types as in the "types" array from the java.io.ObjectInput stream
* named "stream" into variables as named in "names" (for any element
* of "names" that is null, the corresponding value is unmarshalled
* and discarded).
*/
private static boolean writeUnmarshalArguments(IndentingWriter p,
String streamName,
Type[] types,
String[] names)
throws IOException
{
if (types.length != names.length) {
throw new Error("parameter type and name arrays different sizes");
}
boolean readObject = false;
for (int i = 0; i < types.length; i++) {
if (writeUnmarshalArgument(p, streamName, types[i], names[i])) {
readObject = true;
}
p.pln(";");
}
return readObject;
}
/**
* Return a snippet of Java code to wrap a value named "name" of
* type "type" into an object as appropriate for use by the
* Java Reflection API.
*
* For primitive types, an appropriate wrapper class instantiated
* with the primitive value. For object types (including arrays),
* no wrapping is necessary, so the value is named directly.
*/
private static String wrapArgumentCode(Type type, String name) {
int typeCode = type.getTypeCode();
switch (typeCode) {
case TC_BOOLEAN:
return ("(" + name +
" ? java.lang.Boolean.TRUE : java.lang.Boolean.FALSE)");
case TC_BYTE:
return "new java.lang.Byte(" + name + ")";
case TC_CHAR:
return "new java.lang.Character(" + name + ")";
case TC_SHORT:
return "new java.lang.Short(" + name + ")";
case TC_INT:
return "new java.lang.Integer(" + name + ")";
case TC_LONG:
return "new java.lang.Long(" + name + ")";
case TC_FLOAT:
return "new java.lang.Float(" + name + ")";
case TC_DOUBLE:
return "new java.lang.Double(" + name + ")";
case TC_ARRAY:
case TC_CLASS:
return name;
default:
throw new Error("unexpected type code: " + typeCode);
}
}
/**
* Return a snippet of Java code to unwrap a value named "name" into
* a value of type "type", as appropriate for the Java Reflection API.
*
* For primitive types, the value is assumed to be of the corresponding
* wrapper type, and a method is called on the wrapper type to retrieve
* the primitive value. For object types (include arrays), no
* unwrapping is necessary; the value is simply cast to the expected
* real object type.
*/
private static String unwrapArgumentCode(Type type, String name) {
int typeCode = type.getTypeCode();
switch (typeCode) {
case TC_BOOLEAN:
return "((java.lang.Boolean) " + name + ").booleanValue()";
case TC_BYTE:
return "((java.lang.Byte) " + name + ").byteValue()";
case TC_CHAR:
return "((java.lang.Character) " + name + ").charValue()";
case TC_SHORT:
return "((java.lang.Short) " + name + ").shortValue()";
case TC_INT:
return "((java.lang.Integer) " + name + ").intValue()";
case TC_LONG:
return "((java.lang.Long) " + name + ").longValue()";
case TC_FLOAT:
return "((java.lang.Float) " + name + ").floatValue()";
case TC_DOUBLE:
return "((java.lang.Double) " + name + ").doubleValue()";
case TC_ARRAY:
case TC_CLASS:
return "((" + type + ") " + name + ")";
default:
throw new Error("unexpected type code: " + typeCode);
}
}
}
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