How to add persistence (“memory”) to your graph

Many AI applications need memory to share context across multiple interactions. In LangGraph4j, memory is provided for any StateGraph through Checkpointers.

When creating any LangGraph workflow, you can set them up to persist their state by doing using the following:

A Checkpointer, such as the MemorySaver
Pass your Checkpointers in configuration when compiling the graph.

String userHomeDir = System.getProperty("user.home");
String localRespoUrl = "file://" + userHomeDir + "/.m2/repository/";
String langchain4jVersion = "0.35.0"

%dependency /add-repo local \{localRespoUrl} release|never snapshot|always
%dependency /list-repos

[0mRepository [1m[32mlocal[0m url: [1m[32mfile:///Users/bsorrentino/.m2/repository/[0m added.
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[0m[0mname: [1m[32mjboss [0murl: [1m[32mhttps://repository.jboss.org/nexus/content/repositories/releases/ [0mrelease:[32mtrue [0mupdate:[32mnever [0msnapshot:[32mfalse [0mupdate:[32mnever 
[0m[0mname: [1m[32matlassian [0murl: [1m[32mhttps://packages.atlassian.com/maven/public [0mrelease:[32mtrue [0mupdate:[32mnever [0msnapshot:[32mfalse [0mupdate:[32mnever 
[0m[0mname: [1m[32mlocal [0murl: [1m[32mfile:///Users/bsorrentino/.m2/repository/ [0mrelease:[32mtrue [0mupdate:[32mnever [0msnapshot:[32mtrue [0mupdate:[32malways 
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%dependency /add org.bsc.langgraph4j:langgraph4j-core-jdk8:1.0-SNAPSHOT
%dependency /add org.bsc.langgraph4j:langgraph4j-langchain4j:1.0-SNAPSHOT
%dependency /add dev.langchain4j:langchain4j:\{langchain4jVersion}
%dependency /add dev.langchain4j:langchain4j-open-ai:\{langchain4jVersion}

%dependency /resolve

Adding dependency [0m[1m[32morg.bsc.langgraph4j:langgraph4j-core-jdk8:1.0-SNAPSHOT
[0mAdding dependency [0m[1m[32morg.bsc.langgraph4j:langgraph4j-langchain4j:1.0-SNAPSHOT
[0mAdding dependency [0m[1m[32mdev.langchain4j:langchain4j:0.35.0
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Resolved artifacts count: 25
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