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* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
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*
* http://www.apache.org/licenses/LICENSE-2.0
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package org.apache.cayenne.dba;
import org.apache.cayenne.di.DIRuntimeException;
import java.util.Map;
import java.util.Objects;
/**
* An injectable provider that returns a given service in a context of a specific {@link DbAdapter}.
* This allows modules to create adapter-specific extensions without altering DbAdapter API.
*
* @since 4.0
*/
public class PerAdapterProvider<T> {
private Map<String, T> perAdapterValues;
private T defaultValue;
public PerAdapterProvider(Map<String, T> perAdapterValues, T defaultValue) {
this.perAdapterValues = Objects.requireNonNull(perAdapterValues);
this.defaultValue = Objects.requireNonNull(defaultValue);
}
public T get(DbAdapter adapter) throws DIRuntimeException {
T t = perAdapterValues.get(adapter.unwrap().getClass().getName());
return t != null ? t : defaultValue;
}
}