StemmerModelRegistry.java

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package org.egothor.stemmer;

import java.io.BufferedReader;

import java.io.IOException;

import java.io.InputStream;

import java.io.InputStreamReader;

import java.net.URL;

import java.nio.charset.StandardCharsets;

import java.util.ArrayList;

import java.util.Collections;

import java.util.Enumeration;

import java.util.LinkedHashMap;

import java.util.List;

import java.util.Map;

import java.util.Objects;

import java.util.Properties;

/**

 * Immutable deterministic registry of models discovered from classpath indexes.

 *

 * <p>Discovery enumerates every {@value #INDEX_RESOURCE} visible to the selected

 * class loader, validates the referenced descriptors, sorts them by stable model

 * identifier, and rejects duplicate identifiers. Selection never depends on

 * classpath order. Registry creation validates metadata and resource presence;

 * {@link StemmerPatchTrieLoader} verifies resource bytes when loading a model.</p>

 *

 * <p>Registry creation is not globally cached. Applications should normally

 * discover once for a class-loader scope and retain the immutable result.</p>

 */

@SuppressWarnings({ "PMD.UseProperClassLoader", "PMD.ControlStatementBraces" })

public final class StemmerModelRegistry {

    /** Fixed classpath index name used by every model artifact. */

    public static final String INDEX_RESOURCE = "META-INF/radixor/models.index";

    private static final String FORMAT = "radixor-dictionary-tsv-gzip";

    private static final int FORMAT_VERSION = 1;

    private final Map<String, StemmerModelDescriptor> descriptors;

    /** Creates an immutable registry from already validated descriptors. */

    /**

     * Discovers models through the current thread context class loader.

     *

     * <p>If the context loader is {@code null}, the defining class loader of this

     * registry is used.</p>

     *

     * @return immutable registry in stable model-ID order

     * @throws IOException if index or descriptor resources cannot be enumerated or read

     * @throws DuplicateStemmerModelException if two descriptors declare one model ID

     * @throws StemmerModelIntegrityException if an index, descriptor, or declared resource is invalid

     * @throws UnsupportedStemmerModelFormatException if a descriptor uses an unsupported format

     */

    public static StemmerModelRegistry fromContextClassLoader() throws IOException {

    }

    /**

     * Discovers and validates every indexed descriptor visible to an explicit class loader.

     *

     * @param classLoader class loader whose indexed model resources are visible

     * @return immutable registry in stable model-ID order

     * @throws NullPointerException if {@code classLoader} is {@code null}

     * @throws IOException if index or descriptor resources cannot be enumerated or read

     * @throws DuplicateStemmerModelException if two descriptors declare one model ID

     * @throws StemmerModelIntegrityException if an index, descriptor, or declared resource is invalid

     * @throws UnsupportedStemmerModelFormatException if a descriptor uses an unsupported format

     */

    public static StemmerModelRegistry fromClassLoader(final ClassLoader classLoader) throws IOException {

            }

    }

    /** Returns all descriptors in stable model-identifier order. */

    /**

     * Returns the model with an exact stable identifier.

     *

     * @param modelId exact stable model identifier

     * @return matching descriptor

     * @throws NullPointerException if {@code modelId} is {@code null}

     * @throws StemmerModelNotFoundException if the selected class loader exposes no matching descriptor

     */

    public StemmerModelDescriptor require(final String modelId) {

                    + modelId + ":<version> to the runtime classpath.");

        }

    }

    /**

     * Returns all models for a language in stable model-identifier order.

     *

     * @param language language to filter

     * @return immutable list, possibly empty

     * @throws NullPointerException if {@code language} is {@code null}

     */

    public List<StemmerModelDescriptor> findByLanguage(final StemmerPatchTrieLoader.Language language) {

    }

    /**

     * Resolves the language's documented default model without classpath-order fallback.

     *

     * @param language language whose {@link StemmerPatchTrieLoader.Language#defaultModelId()} is required

     * @return exact default-model descriptor

     * @throws NullPointerException if {@code language} is {@code null}

     * @throws StemmerModelNotFoundException if the default model is not visible

     * @throws StemmerModelIntegrityException if the default descriptor declares another language

     */

    public StemmerModelDescriptor requireDefault(final StemmerPatchTrieLoader.Language language) {

                    + "' is available for language " + language + ". Add org.egothor:radixor-model-"

        }

        }

    }

    /** Reads one deterministic index and appends its descriptors. */

    private static void readIndex(final URL index, final ClassLoader classLoader,

            final List<StemmerModelDescriptor> descriptors) throws IOException {

            String line;

                }

    /** Parses and validates one immutable descriptor. */

    private static StemmerModelDescriptor readDescriptor(final URL source, final ClassLoader classLoader) throws IOException {

        final int version;

        final StemmerPatchTrieLoader.Language language;

    }

    /** Returns a required nonblank property. */

    private static String required(final Properties properties, final String key, final URL source) {

    }

}

Mutations

1.1
Location : fromContextClassLoader
Killed by : none negated conditional → SURVIVED Covering tests

2.2
Location : fromContextClassLoader
Killed by : org.egothor.stemmer.StemmerModelRegistryTest.[engine:junit-jupiter]/[class:org.egothor.stemmer.StemmerModelRegistryTest]/[method:discoversModelsDeterministically()] replaced return value with null for org/egothor/stemmer/StemmerModelRegistry::fromContextClassLoader → KILLED

1.1
Location : fromClassLoader
Killed by : none removed call to java/util/List::sort → SURVIVED Covering tests

2.2
Location : lambda$fromClassLoader$0
Killed by : none replaced int return with 0 for org/egothor/stemmer/StemmerModelRegistry::lambda$fromClassLoader$0 → SURVIVED Covering tests

1.1
Location : fromClassLoader
Killed by : none removed call to java/util/Collections::sort → SURVIVED Covering tests

1.1
Location : models
Killed by : none replaced return value with Collections.emptyList for org/egothor/stemmer/StemmerModelRegistry::models → SURVIVED Covering tests

1.1
Location : readIndex
Killed by : none Changed increment from 1 to -1 → SURVIVED Covering tests