Add warning before recovery operation starts, Fix #308

docs/archived/README.md

@@ -414,7 +414,7 @@ ChronicleMap<Integer, PostalCodeRange> cityPostalCodes = ChronicleMap
 
 If the Chronicle Map is configured to store entry checksums along with entries, recovery procedure
 checks for each entry that the checksums is correct, otherwise it assumes the entry is corrupted and
-deletes it from the Chronicle Map. If checksums are to stored, recovery procedure cannot guarantee
+deletes it from the Chronicle Map. If checksums are not stored, recovery procedure cannot guarantee
 correctness of entry data. See [Entry checksums](#entry-checksums) section for more information.
 
 #### Key and Value Types

src/main/java/net/openhft/chronicle/map/ChronicleMapBuilder.java

@@ -48,8 +48,6 @@ import net.openhft.chronicle.wire.TextWire;
 import net.openhft.chronicle.wire.Wire;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
 
 import java.io.*;
 import java.lang.reflect.InvocationTargetException;
@@ -1833,6 +1831,12 @@ public final class ChronicleMapBuilder<K, V> implements
                                                               final boolean recover,
                                                               final boolean overrideBuilderConfig,
                                                               @Nullable final ChronicleHashCorruption.Listener corruptionListener) throws IOException {
+
+        if (recover) {
+            Jvm.warn().on(ChronicleMapBuilder.class, "Recovery operation needs exclusive access to the ChronicleMap or else the result is unspecified including the risk of loosing and/or corrupting partial or all data.");
+            Jvm.warn().on(ChronicleMapBuilder.class, "Do not use recovery as a standard way of opening a ChronicleMap.");
+        }
+
         final ChronicleHashCorruptionImpl corruption = recover ? new ChronicleHashCorruptionImpl() : null;
         try {
             int headerSize = waitUntilReady(raf, file, recover);