Snippet

Managing Transient State Memory with ObjectProvider and Prototype Scopes

Injecting ObjectProvider instead of direct prototype beans avoids holding long-lived references inside singleton services. This pattern lazily instantiates stateful objects on demand and allows the JVM garbage collector to reclaim large internal buffers as soon as local execution finishes.

snippet.java

java

@Component
@Scope(ConfigurableBeanFactory.SCOPE_PROTOTYPE)
public class HeavyReportProcessor {
    private final byte[] scratchBuffer = new byte[1024 * 1024]; // 1MB buffer
 
    public void process(ReportRequest request) {
        // Heavy stateful processing
    }
}
 
@Service
public class ReportManager {
    private final ObjectProvider<HeavyReportProcessor> processorProvider;
 
    public ReportManager(ObjectProvider<HeavyReportProcessor> processorProvider) {
        this.processorProvider = processorProvider;
    }
 
    public void handleReport(ReportRequest request) {
        HeavyReportProcessor processor = processorProvider.getObject();
        try {
            processor.process(request);
        } finally {
            // Discard reference immediately for GC collection
            processor = null;
        }
    }
}

spring

Breakdown

@Scope(ConfigurableBeanFactory.SCOPE_PROTOTYPE)

Instructs Spring to instantiate a fresh, independent instance with separate heap allocation for each request.

private final ObjectProvider<HeavyReportProcessor> processorProvider;

Provides on-demand lazy factory retrieval of prototype beans without creating circular or retained references in singletons.

HeavyReportProcessor processor = processorProvider.getObject();

Constructs a new transient instance scoped to the local stack frame.

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Managing Transient State Memory with ObjectProvider and Prototype Scopes

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