Core/src/main/java/fr/altarik/toolbox/core/builder/EmptyCollectionException.java

@@ -0,0 +1,8 @@
+package fr.altarik.toolbox.core.builder;
+
+public class EmptyCollectionException extends NullPointerException {
+
+    public EmptyCollectionException(String message) {
+        super(message);
+    }
+}

Core/src/main/java/fr/altarik/toolbox/core/builder/IBuilder.java

@@ -0,0 +1,11 @@
+package fr.altarik.toolbox.core.builder;
+
+public interface IBuilder<T> {
+
+    /**
+     * Build the builders parameters into T object
+     * @return The created objects thanks to given parameters
+     * @throws Exception if any error occur during creation of the built object
+     */
+    T build() throws Exception;
+}

Core/src/main/java/fr/altarik/toolbox/core/builder/IParamBuilder.java

@@ -0,0 +1,24 @@
+package fr.altarik.toolbox.core.builder;
+
+/**
+ * Builder parameter, for more flexibility
+ * @param <T> the parameter type
+ * @see OptionalParamBuilder
+ * @see RequiredParamBuilder
+ * @see RequiredCollectionParameterBuilder
+ */
+public interface IParamBuilder<T> {
+
+    /**
+     * Get the given object, may return {@link NullPointerException} depending on the policy of implemented class
+     * @return the parameter given by {@link IParamBuilder#set(Object)}
+     * @throws NullPointerException may throw this error depending on the policy of implemented class
+     */
+    T get() throws NullPointerException;
+
+    /**
+     * Change/insert the value of the parameter
+     * @param parameter the given parameter
+     */
+    void set(T parameter);
+}

Core/src/main/java/fr/altarik/toolbox/core/builder/OptionalParamBuilder.java

@@ -0,0 +1,24 @@
+package fr.altarik.toolbox.core.builder;
+
+/**
+ * Doesn't throw a {@link NullPointerException} when using {@link IParamBuilder#get()} in any case
+ * @param <T> the returned type
+ * @see IParamBuilder
+ */
+public class OptionalParamBuilder<T> implements IParamBuilder<T> {
+
+    private T parameter;
+
+    public OptionalParamBuilder(T param) {
+        this.parameter = param;
+    }
+    @Override
+    public T get() throws NullPointerException {
+        return parameter;
+    }
+
+    @Override
+    public void set(T parameter) {
+        this.parameter = parameter;
+    }
+}

Core/src/main/java/fr/altarik/toolbox/core/builder/RequiredCollectionParameterBuilder.java

@@ -0,0 +1,52 @@
+package fr.altarik.toolbox.core.builder;
+
+import org.jetbrains.annotations.NotNull;
+
+import java.util.Collection;
+import java.util.Objects;
+
+/**
+ * Mostly same as {@link RequiredParamBuilder} but for list
+ * @param <E> The type contained in the collection
+ * @param <T> The returned type
+ */
+public class RequiredCollectionParameterBuilder<E, T extends Collection<E>> implements IParamBuilder<T> {
+
+    private final T collection;
+    private final boolean canBeEmpty;
+
+    public RequiredCollectionParameterBuilder(@NotNull T collection, boolean canBeEmpty) {
+        this.collection = Objects.requireNonNull(collection);
+        this.canBeEmpty = canBeEmpty;
+    }
+
+    /**
+     * <p>Return the list, if not empty</p>
+     * <p>If empty, return the collection if {@code canBeEmpty} if true, otherwise throw a {@link NullPointerException}</p>
+     * @return the collection
+     * @throws NullPointerException if collection is empty and {@code canBeEmpty} is false
+     */
+    @Override
+    public T get() throws NullPointerException {
+        if(canBeEmpty) {
+            return collection;
+        } else if(!collection.isEmpty()) {
+            return collection;
+        } else {
+            throw new EmptyCollectionException("Collection cannot be empty");
+        }
+    }
+
+    @Override
+    public void set(T parameter) {
+        throw new UnsupportedOperationException("Use `add` in place of `set` for RequiredCollectionParameterBuilder");
+    }
+
+    /**
+     * Add an element to the collection
+     * @param element element to add to the list
+     */
+    public void add(E element) {
+        collection.add(element);
+    }
+}

Core/src/main/java/fr/altarik/toolbox/core/builder/RequiredParamBuilder.java

@@ -0,0 +1,30 @@
+package fr.altarik.toolbox.core.builder;
+
+import java.util.Objects;
+
+/**
+ * Throw a {@link NullPointerException} when using {@link IParamBuilder#get()} if the parameter doesn't have been initialized
+ * @param <T> the returned type
+ */
+public class RequiredParamBuilder<T> implements IParamBuilder<T> {
+
+    private T parameter;
+
+    public RequiredParamBuilder(T parameter) {
+        this.parameter = parameter;
+    }
+
+    public RequiredParamBuilder() {
+        this(null);
+    }
+
+    @Override
+    public T get() {
+        return Objects.requireNonNull(parameter);
+    }
+
+    @Override
+    public void set(T parameter) {
+        this.parameter = parameter;
+    }
+}

Core/src/test/java/BuilderImpl.java

@@ -0,0 +1,38 @@
+import fr.altarik.toolbox.core.builder.IBuilder;
+import fr.altarik.toolbox.core.builder.RequiredCollectionParameterBuilder;
+import fr.altarik.toolbox.core.builder.RequiredParamBuilder;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public class BuilderImpl implements IBuilder<BuilderResult> {
+
+    private final RequiredCollectionParameterBuilder<String, List<String>> collection;
+    private final RequiredParamBuilder<Integer> numberOfSentences;
+
+    private BuilderImpl(boolean canBeEmpty) {
+        this.collection = new RequiredCollectionParameterBuilder<>(new ArrayList<>(), canBeEmpty);
+        this.numberOfSentences = new RequiredParamBuilder<>();
+    }
+
+    public BuilderImpl addSentence(String sentence) {
+        collection.add(sentence);
+        return this;
+    }
+
+    public BuilderImpl numberOfSentence(int i) {
+        this.numberOfSentences.set(i);
+        return this;
+    }
+
+    public static BuilderImpl builder(boolean canBeEmpty) {
+        return new BuilderImpl(canBeEmpty);
+    }
+
+
+
+    @Override
+    public BuilderResult build() throws Exception {
+        return new BuilderResult(collection.get(), numberOfSentences.get());
+    }
+}

Core/src/test/java/BuilderResult.java

@@ -0,0 +1,5 @@
+import java.util.List;
+
+public record BuilderResult(List<String> sentences, int numberOfSentences) {
+
+}

Core/src/test/java/BuilderTest.java

@@ -0,0 +1,32 @@
+import fr.altarik.toolbox.core.builder.EmptyCollectionException;
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.Test;
+
+import java.util.Arrays;
+
+public class BuilderTest {
+
+
+    @Test
+    void builderTest() throws Exception {
+        BuilderImpl builder = BuilderImpl.builder(true);
+        builder.addSentence("First sentence");
+        builder.addSentence("Second sentence");
+        builder.numberOfSentence(2);
+        BuilderResult res = builder.build();
+        Assertions.assertEquals(Arrays.asList("First sentence", "Second sentence"), res.sentences());
+        Assertions.assertEquals(res.numberOfSentences(), 2);
+
+        BuilderImpl builder1 = BuilderImpl.builder(false);
+        builder1.numberOfSentence(3);
+        Assertions.assertThrowsExactly(EmptyCollectionException.class, builder1::build);
+
+        BuilderImpl builder2 = BuilderImpl.builder(true);
+        builder2.numberOfSentence(3);
+        Assertions.assertDoesNotThrow(builder2::build);
+
+        BuilderImpl builder3 = BuilderImpl.builder(true);
+        Assertions.assertThrowsExactly(NullPointerException.class, builder3::build);
+    }
+
+}

Database/build.gradle

@@ -1,6 +1,7 @@
 dependencies {
     implementation 'org.postgresql:postgresql:42.5.0'
     testImplementation 'com.google.code.gson:gson:2.10'
+    implementation project(':Core')
 }
 
 test {

Database/src/main/java/fr/altarik/toolbox/database/keyvalue/KeyValueBuilder.java

@@ -1,5 +1,8 @@
 package fr.altarik.toolbox.database.keyvalue;
 
+import fr.altarik.toolbox.core.builder.IBuilder;
+import fr.altarik.toolbox.core.builder.RequiredCollectionParameterBuilder;
+import fr.altarik.toolbox.core.builder.RequiredParamBuilder;
 import fr.altarik.toolbox.database.SqlConnection;
 import net.minecraft.util.Pair;
 import org.jetbrains.annotations.NotNull;
@@ -11,20 +14,30 @@ import java.util.ArrayList;
 import java.util.List;
 import java.util.Objects;
 
-public class KeyValueBuilder {
+public class KeyValueBuilder implements IBuilder<KeyValueConnection> {
 
-    private final String tableName;
-    private final List<AdditionalColumn> additionalColumns;
-    private final SqlConnection connection;
+    private final RequiredParamBuilder<String> tableName;
+    private final RequiredCollectionParameterBuilder<AdditionalColumn, List<AdditionalColumn>> additionalColumns;
+    private final RequiredParamBuilder<SqlConnection> connection;
 
-    private KeyValueBuilder(SqlConnection connection, String tableName) {
-        this.connection = connection;
-        this.tableName = tableName;
-        this.additionalColumns = new ArrayList<>();
+    private KeyValueBuilder() {
+        this.tableName = new RequiredParamBuilder<>();
+        this.connection = new RequiredParamBuilder<>();
+        this.additionalColumns = new RequiredCollectionParameterBuilder<>(new ArrayList<>(), true);
     }
 
-    public static KeyValueBuilder builder(@NotNull SqlConnection connection, @NotNull String tableName) {
-        return new KeyValueBuilder(connection, tableName);
+    public static KeyValueBuilder builder() {
+        return new KeyValueBuilder();
+    }
+
+    public KeyValueBuilder setConnection(@NotNull SqlConnection connection) {
+        this.connection.set(connection);
+        return this;
+    }
+
+    public KeyValueBuilder setTableName(@NotNull String tableName) {
+        this.tableName.set(tableName);
+        return this;
     }
 
     public KeyValueBuilder addColumn(AdditionalColumn additionalColumn) {
@@ -33,7 +46,7 @@ public class KeyValueBuilder {
     }
 
     public KeyValueConnection build() throws SQLException {
-        return new KeyValueConnection(connection, tableName, additionalColumns);
+        return new KeyValueConnection(connection.get(), tableName.get(), additionalColumns.get());
     }
 
     public record AdditionalColumn(@NotNull String columnName, @NotNull JDBCType type, boolean notNull, @Nullable AdditionalColumnReference reference) {

Database/src/test/java/fr/altarik/toolbox/database/ConnectionTest.java

@@ -30,6 +30,7 @@ class ConnectionTest {
             try(PreparedStatement statement = connection.getConnection().prepareStatement("CREATE TABLE IF NOT EXISTS toolbox(id SERIAL, PRIMARY KEY (id));")) {
                 statement.executeUpdate();
             }
+            connection.close();
         });
     }
 

settings.gradle

@@ -10,4 +10,4 @@ pluginManagement {
 }
 
 rootProject.name = 'Toolbox'
-include(':Tasks', ':Database', ':Pagination')
+include(':Tasks', ':Database', ':Pagination', ':Core')