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Questions tagged [mapdb]

MapDB provides concurrent Maps, Sets and Queues backed by disk storage or off-heap memory

MapDB provides concurrent Maps, Sets and Queues backed by disk storage or off-heap memory. It is a fast and easy to use embedded Java database engine. And it is completely free under Apache License. MapDB is free as speech and free as beer under Apache License 2.0.

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gwt javax.servlet.ServletContext log: Exception while dispatching incoming RPC call creating mapdb db

Hi i take the MyWEbApp of GWT and tryed ok it worked, i needed to make a mapdb database, I imported mapDB and only added in server: File utilizzo = new File("tipregotipregotiprego"); DB db; db =…
Filippo Winston Maccarelli
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MapDB doesn't accept Serializer when creating CircularQueue

When I create circular queue in direct memory. What I have done: BlockingQueue queue =…
Majid Azimi
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Error creating map in MapDB: ClassCastException: [J cannot be cast to [B

I am using MapDB, and attempting to create a direct-memory map, using long-arrays as keys, and I am getting the following error: java.lang.ClassCastException: [J cannot be cast to [B at org.mapdb.Hasher$2.hashCode(Hasher.java:46) at…
MukRaker
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How to use byte array as a key in MapDB's implementation of BTreeMap

Is there any way to use byte array as a key in BTreeMap like this: BTreeMap myBTreeMap = db.getTreeMap("myBTreeMap"); Currently this exception is thrown when trying to put new object into the map: Exception in thread "main"…
PrimosK
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Out of memory w/ mapdb

I'm getting an out of memory error when testing mapdb. Given that the whole idea of the project is to serialize data structures to disk and avoid memory problems, I figure I'm doing something wrong. Any ideas what I'm doing wrong? Or is there a…
Ben Mathews
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MapDB file based db with cache

Using MapDB and unable to find the documentation for the behaviour below. I have the following configuration: DB db = DBMaker.fileDB("cache.db") .closeOnJvmShutdown() .fileMmapEnable() …
user1189332
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mapdb as a request scoped globally available state store?

has anyone used mapdb as a state store in spring boot for a request lifecycle ? I mean set things like "isDebug", etc in mapdb for the particular request and then clear it out at the end of the request ? mapdb sounds very much like how Redux, etc is…
Sandeep
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Why MapDB is slower than LMDB and RocksDB?

I am testing the read performance of MapDB, LMDB and RocksDB. I am inserting 762207 data into these databases and trying to read a value from the databases using JMH(Java Micro Harashment). These are the results Benchmark results I want to know why…
Awdsa
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How to reboot application without losing the TreeMap kept in memory?

In a Spring Boot application, I keep a TreeMap in memory. I'm doing around 10,000 operations per second, and it may increase. To improve performance, I kept data in memory. I want my app to be able to start from the same state when application is…
T. Ç
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Is it possible to create clusters in MapDB?

I have several questions regarding mapdb: Can I configure clusters in mapdb? Because I didnt find any blogs about that so I guess it doesnt offer that Several sources say that MapDB is scalable but what is exactly scalable? As far as I understand I…
user12541507
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how to solve problems with persistence mapDB?

i am doing my project with GWT and Madb. The problem is that MapDb every time it deletes the contents of the db. How can I do to keep the db persistent?
Fede_23
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Why MapDB is not working with kotlin but works with Java?

I am new in Kotlin. I can't understand why Map DB is not working for me with kotlin. I tried google but it was no help. gradle dependencies { compile(kotlin("stdlib-jdk8")) implementation(group="org.mapdb", name= "mapdb", version= "3.0.7") …
user6457056
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Java cache library mapdb expire max size

I'd like to use mapdb library to cache max n object. I wrote something like this: DB dbMemory = DBMaker .memoryDB() .make(); HTreeMap inMemory = dbMemory .hashMap("inMemory", Serializer.LONG,…
JohnyBe
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MapDB list type?

I am using mapdb 3.0.7 I see various hash map and tree map storage types here. But I have a use case that needs a List to be persisted to mapdb. Does this version of mapDB even support this?
Nicholas DiPiazza
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MapDB treemap.clear() takes forever

I have treemap in mapdb with 150K entries. Calling treemap.clear() takes minutes. How can I do this quickly? Creating new one with db.treeMap("pageCache").create(); gives crash org.mapdb.DBException$WrongConfiguration: Named record already exists:…
Stepan Yakovenko
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