Additional change for OPENDJ-354: Implement a RequestHandler which provides...

Matthew Swift

03.37.2013 47767a61b7b8702fbe81951213e27b7816dff7d5

Additional change for OPENDJ-354: Implement a RequestHandler which provides an in-memory backend

* invoke result handlers outside of locks in order to avoid potential deadlocks when chaining updates from within a search result handler
* remove read lock.

 opendj3/opendj-ldap-sdk/src/main/java/org/forgerock/opendj/ldap/MemoryBackend.java

@@ -35,7 +35,6 @@
import java.io.IOException;
import java.util.NavigableMap;
import java.util.concurrent.ConcurrentSkipListMap;
import java.util.concurrent.locks.ReentrantReadWriteLock;

import org.forgerock.i18n.LocalizedIllegalArgumentException;
import org.forgerock.opendj.ldap.controls.AssertionRequestControl;
@@ -94,7 +93,7 @@
public final class MemoryBackend implements RequestHandler<RequestContext> {
    private final DecodeOptions decodeOptions;
    private final ConcurrentSkipListMap<DN, Entry> entries = new ConcurrentSkipListMap<DN, Entry>();
    private final ReentrantReadWriteLock entryLock = new ReentrantReadWriteLock();
    private final Object writeLock = new Object();
    private final Schema schema;

    /**
@@ -165,23 +164,22 @@
    public void handleAdd(final RequestContext requestContext, final AddRequest request,
            final IntermediateResponseHandler intermediateResponseHandler,
            final ResultHandler<? super Result> resultHandler) {
        entryLock.writeLock().lock();
        try {
            synchronized (writeLock) {
            final DN dn = request.getName();
            final DN parent = dn.parent();
            if (entries.containsKey(dn)) {
                throw newErrorResult(ResultCode.ENTRY_ALREADY_EXISTS, "The entry '" + dn.toString()
                        + "' already exists");
                    throw newErrorResult(ResultCode.ENTRY_ALREADY_EXISTS, "The entry '"
                            + dn.toString() + "' already exists");
            } else if (!entries.containsKey(parent)) {
                noSuchObject(parent);
            } else {
                entries.put(dn, request);
                resultHandler.handleResult(getResult(request, null, request));
            }
            }
            resultHandler.handleResult(getResult(request, null, request));
        } catch (final ErrorResultException e) {
            resultHandler.handleErrorResult(e);
        } finally {
            entryLock.writeLock().unlock();
        }
    }

@@ -190,8 +188,9 @@
            final BindRequest request,
            final IntermediateResponseHandler intermediateResponseHandler,
            final ResultHandler<? super BindResult> resultHandler) {
        entryLock.readLock().lock();
        try {
            final Entry entry;
            synchronized (writeLock) {
            final DN username = DN.valueOf(request.getName(), schema);
            final byte[] password;
            if (request instanceof SimpleBindRequest) {
@@ -204,12 +203,12 @@
                        "non-SIMPLE authentication not supported: "
                                + request.getAuthenticationType());
            }
            final Entry entry = getRequiredEntry(null, username);
            if (entry.containsAttribute("userPassword", password)) {
                resultHandler.handleResult(getBindResult(request, entry, entry));
            } else {
                entry = getRequiredEntry(null, username);
                if (!entry.containsAttribute("userPassword", password)) {
                throw newErrorResult(ResultCode.INVALID_CREDENTIALS, "Wrong password");
            }
            }
            resultHandler.handleResult(getBindResult(request, entry, entry));
        } catch (final LocalizedIllegalArgumentException e) {
            resultHandler.handleErrorResult(newErrorResult(ResultCode.PROTOCOL_ERROR, e));
        } catch (final EntryNotFoundException e) {
@@ -222,8 +221,6 @@
                    "Unknown user"));
        } catch (final ErrorResultException e) {
            resultHandler.handleErrorResult(e);
        } finally {
            entryLock.readLock().unlock();
        }
    }

@@ -231,19 +228,20 @@
    public void handleCompare(final RequestContext requestContext, final CompareRequest request,
            final IntermediateResponseHandler intermediateResponseHandler,
            final ResultHandler<? super CompareResult> resultHandler) {
        entryLock.readLock().lock();
        try {
            final Entry entry;
            final Attribute assertion;
            synchronized (writeLock) {
            final DN dn = request.getName();
            final Entry entry = getRequiredEntry(request, dn);
            final Attribute assertion =
                entry = getRequiredEntry(request, dn);
                assertion =
                    singletonAttribute(request.getAttributeDescription(), request
                            .getAssertionValue());
            }
            resultHandler.handleResult(getCompareResult(request, entry, entry.containsAttribute(
                    assertion, null)));
        } catch (final ErrorResultException e) {
            resultHandler.handleErrorResult(e);
        } finally {
            entryLock.readLock().unlock();
        }
    }

@@ -251,10 +249,11 @@
    public void handleDelete(final RequestContext requestContext, final DeleteRequest request,
            final IntermediateResponseHandler intermediateResponseHandler,
            final ResultHandler<? super Result> resultHandler) {
        entryLock.writeLock().lock();
        try {
            final Entry entry;
            synchronized (writeLock) {
            final DN dn = request.getName();
            final Entry entry = getRequiredEntry(request, dn);
                entry = getRequiredEntry(request, dn);
            if (request.getControl(SubtreeDeleteRequestControl.DECODER, decodeOptions) != null) {
                // Subtree delete.
                entries.subMap(dn, dn.child(RDN.maxValue())).clear();
@@ -267,13 +266,12 @@
                    throw newErrorResult(ResultCode.NOT_ALLOWED_ON_NONLEAF);
                }
            }
            }
            resultHandler.handleResult(getResult(request, entry, null));
        } catch (final DecodeException e) {
            resultHandler.handleErrorResult(newErrorResult(ResultCode.PROTOCOL_ERROR, e));
        } catch (final ErrorResultException e) {
            resultHandler.handleErrorResult(e);
        } finally {
            entryLock.writeLock().unlock();
        }
    }

@@ -290,17 +288,18 @@
    public void handleModify(final RequestContext requestContext, final ModifyRequest request,
            final IntermediateResponseHandler intermediateResponseHandler,
            final ResultHandler<? super Result> resultHandler) {
        entryLock.writeLock().lock();
        try {
            final Entry entry;
            final Entry newEntry;
            synchronized (writeLock) {
            final DN dn = request.getName();
            final Entry entry = getRequiredEntry(request, dn);
            final Entry newEntry = new LinkedHashMapEntry(entry);
                entry = getRequiredEntry(request, dn);
                newEntry = new LinkedHashMapEntry(entry);
            entries.put(dn, modifyEntry(newEntry, request));
            }
            resultHandler.handleResult(getResult(request, entry, newEntry));
        } catch (final ErrorResultException e) {
            resultHandler.handleErrorResult(e);
        } finally {
            entryLock.writeLock().unlock();
        }
    }

@@ -316,7 +315,6 @@
    public void handleSearch(final RequestContext requestContext, final SearchRequest request,
            final IntermediateResponseHandler intermediateResponseHandler,
            final SearchResultHandler resultHandler) {
        entryLock.readLock().lock();
        try {
            final DN dn = request.getName();
            final Entry baseEntry = getRequiredEntry(request, dn);
@@ -364,8 +362,6 @@
            resultHandler.handleResult(newResult(ResultCode.SUCCESS));
        } catch (final ErrorResultException e) {
            resultHandler.handleErrorResult(e);
        } finally {
            entryLock.readLock().unlock();
        }
    }