ISSUE-16058: PIP-177: Add the classLoader field for SchemaDefinition

[sijie]

Original Issue: apache#16058

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Motivation

Now, don‘t register logical type conversions when use SchemaDefinition.<T>builder().withJsonDef() to create the schema, beacase it without classLoader param. (e.g: apache#15899)

See: https://github.com/apache/pulsar/blob/04aa9e8e51869d1621a7e25402a656084eebfc09/pulsar-client/src/main/java/org/apache/pulsar/client/impl/schema/reader/AvroReader.java#L58-L68

We can add the classLoader field for SchemaDefinition, user can manually pass a classLoader to register logical type conversions

Goal

This proposes to add the classLoader field for SchemaDefinition. When using SchemaDefinition.<T>builder().withJsonDef() to create the schema it must manually specify a classLoader otherwise, the converter will not work.

The priority of the classLoader field will be higher than by the pojoClass.getClassLoader().

API Changes

public class SchemaDefinition {
    //....

    /**
     * Set schema of pojo classLoader.
     *
     * @param classLoader pojo classLoader
     *
     * @return schema definition builder
     */
    SchemaDefinitionBuilder<T> withClassLoader(ClassLoader classLoader);
}

public class SchemaDefinition {
    //....

    /**
     * Get pojo classLoader.
     *
     * @return pojo schema
     */
    ClassLoader getClassLoader();
}

Implementation

Add the classloader field for SchemaDefinition.