Add indexes for sql, add mssql support and enforce database type limits

README.md

@@ -9,6 +9,7 @@ currently examples can be found in the tests of the AP module and the tests of t
   - support adding every variable of the entity as parameter
 - add `upsert` which either inserts the entity if it's not present or updates the already existing entity
 - adding migrations
+- add null and non-null support
 - and plenty more
 
 # Supported types
@@ -52,7 +53,8 @@ The current codebase is not flexible enough to do these wildly different behavio
 but will be supported in the future.
 
 #### any deleteFirst() and any deleteTop*()
-Anything with a limit projection in delete currently doesn't work for Oracle Database, PostgreSQL and SQLite.
+Anything with a limit projection in delete currently doesn't work for Oracle Database, PostgreSQL, SQLite and SQL Server.
+For SQL Server it's TOP instead of LIMIT.
 For SQLite this is a flag that can be enabled during compile, but it's disabled by default.
 For Oracle and Postgres delete with a limit doesn't exist.
 We have to fetch a record first and then delete it (inside a transaction).
@@ -74,25 +76,32 @@ These are the base type conversions:
 | Java Type | SQL type         | Reason / remarks                                                |
 |-----------|------------------|-----------------------------------------------------------------|
 | Boolean   | boolean          | More platforms support boolean than tinyint / bit               |
-| Byte      | smallint         | SQL Server's tinyint is unsigned and PostgresSQL has no tinyint |
+| Byte      | tinyint          | SQL Server's tinyint is unsigned and PostgresSQL has no tinyint |
 | Short     | smallint         | -                                                               |
-| Char      | smallint         | Basically the same as short                                     |
+| Char      | int              | Unlike short, char is unsigned                                  |
 | Integer   | int              | -                                                               |
 | Long      | bigint           | -                                                               |
-| Float     | real             | Some dialects map this as a double precision type               |
+| Float     | real             | MySQL and MariaDB map this as a double precision type           |
 | Double    | double precision | -                                                               |
-| String    | varchar          | -                                                               |
+| String    | varchar          | All dialects support varchar, but it's deprecated on OracleDB   |
 | Byte[]    | varbinary        | Most dialects support varbinary                                 |
 
 And these are the exceptions:
 
-| Java Type | Dialect    | SQL Type |
-|-----------|------------|----------|
-| Boolean   | SQLite     | int      |
-| Boolean   | SQL Server | bit      |
-| Double    | SQL Server | float    |
-| Byte[]    | PostgreSQL | bytea    |
-| Byte[]    | SQLite     | varchar  |
+| Java Type | Dialect    | SQL Type          |
+|-----------|------------|-------------------|
+| Boolean   | SQLite     | int               |
+| Boolean   | SQL Server | bit               |
+| Byte      | PostgreSQL | smallint          |
+| Byte      | SQL Server | smallint          |
+| Char      | MariaDB    | smallint unsigned |
+| Char      | MySQL      | smallint unsigned |
+| Char      | OracleDB   | number(5)         |
+| Double    | SQL Server | float             |
+| String    | OracleDB   | varchar2          |
+| Byte[]    | OracleDB   | raw               |
+| Byte[]    | PostgreSQL | bytea             |
+| Byte[]    | SQLite     | blob              |
 
 # Query syntax
 Assuming we have the following entity called TestEntity:

ap/src/main/java/org/geysermc/databaseutils/processor/EntityManager.java

@@ -26,6 +26,8 @@
 import org.geysermc.databaseutils.processor.info.ColumnInfo;
 import org.geysermc.databaseutils.processor.info.EntityInfo;
 import org.geysermc.databaseutils.processor.info.IndexInfo;
+import org.geysermc.databaseutils.processor.info.IndexInfo.IndexType;
+import org.geysermc.databaseutils.processor.type.LimitsEnforcer;
 import org.geysermc.databaseutils.processor.util.TypeUtils;
 
 final class EntityManager {
@@ -41,6 +43,9 @@ Collection<EntityInfo> processedEntities() {
     }
 
     EntityInfo processEntity(TypeMirror typeMirror) {
+        // todo technically all those meta annotation classes can be moved a separate module you only need during
+        // compile time, instead of including the annotation definitions in runtime as well
+
         var type = MoreTypes.asTypeElement(typeMirror);
 
         var cached = entityInfoByClassName.get(type.getQualifiedName());
@@ -64,7 +69,7 @@ EntityInfo processEntity(TypeMirror typeMirror) {
         var columns = new ArrayList<ColumnInfo>();
 
         Arrays.stream(type.getAnnotationsByType(Index.class))
-                .map(index -> new IndexInfo(index.name(), index.columns(), index.unique()))
+                .map(index -> new IndexInfo(index.name(), index.columns(), index.unique(), index.direction()))
                 .forEach(indexes::add);
 
         for (Element element : type.getEnclosedElements()) {
@@ -84,7 +89,7 @@ EntityInfo processEntity(TypeMirror typeMirror) {
                 continue;
             }
 
-            columns.add(new ColumnInfo(field.getSimpleName(), typeUtils.toBoxedTypeElement(field.asType())));
+            columns.add(new ColumnInfo(field.getSimpleName(), typeUtils.toBoxedTypeElement(field.asType()), field));
 
             if (hasAnnotation(field, Key.class)) {
                 keys.add(field.getSimpleName());
@@ -119,13 +124,16 @@ EntityInfo processEntity(TypeMirror typeMirror) {
         }
 
         if (!keys.isEmpty()) {
-            indexes.add(new IndexInfo("", keys.toArray(new CharSequence[0]), true));
+            indexes.add(new IndexInfo("", keys.toArray(new CharSequence[0]), IndexType.PRIMARY));
         } else {
             // todo just make every column a key
             throw new IllegalStateException("Expected entity to have at least one field marked as key");
         }
 
         var entityInfo = new EntityInfo(tableName, type, columns, indexes, keys);
+
+        new LimitsEnforcer(entityInfo).enforce();
+
         entityInfoByClassName.put(type.getQualifiedName(), entityInfo);
         return entityInfo;
     }

ap/src/main/java/org/geysermc/databaseutils/processor/RepositoryProcessor.java

@@ -10,6 +10,8 @@
 import com.squareup.javapoet.JavaFile;
 import com.squareup.javapoet.TypeSpec;
 import java.io.IOException;
+import java.io.PrintWriter;
+import java.io.StringWriter;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Locale;
@@ -206,21 +208,8 @@ private void error(Element cause, String message, Object... arguments) {
     }
 
     private void error(Element cause, Throwable exception) {
-        // trimming down the exception until the first trace of ourselves.
-        // This would be either a test class or our RepositoryProcessor.
-        // This makes the exception much easier to read
-        int lastOwnTrace = 0;
-        StringBuilder stackTrace = new StringBuilder(exception.toString()).append('\n');
-        for (StackTraceElement traceElement : exception.getStackTrace()) {
-            stackTrace.append(traceElement.toString()).append('\n');
-            if (traceElement.getClassName().startsWith("org.geysermc.databaseutils")) {
-                lastOwnTrace = stackTrace.length() - 1;
-            }
-        }
-
-        if (lastOwnTrace != stackTrace.length() - 1) {
-            stackTrace.delete(lastOwnTrace, stackTrace.length());
-        }
-        this.messager.printMessage(Diagnostic.Kind.ERROR, stackTrace, cause);
+        var writer = new StringWriter();
+        exception.printStackTrace(new PrintWriter(writer));
+        this.messager.printMessage(Diagnostic.Kind.ERROR, writer.toString(), cause);
     }
 }

ap/src/main/java/org/geysermc/databaseutils/processor/info/ColumnInfo.java

@@ -5,16 +5,31 @@
  */
 package org.geysermc.databaseutils.processor.info;
 
+import java.lang.annotation.Annotation;
 import javax.lang.model.element.Name;
 import javax.lang.model.element.TypeElement;
+import javax.lang.model.element.VariableElement;
 import javax.lang.model.type.TypeMirror;
+import org.geysermc.databaseutils.meta.Length;
 
-public record ColumnInfo(Name name, TypeElement type) {
+public record ColumnInfo(Name name, TypeElement type, VariableElement variable) {
     public TypeMirror asType() {
         return type.asType();
     }
 
     public Name typeName() {
         return type.getQualifiedName();
     }
+
+    public <T extends Annotation> T annotation(Class<T> annotationClass) {
+        return variable.getAnnotation(annotationClass);
+    }
+
+    /**
+     * Returns the max length as provided by {@link Length}, or -1 if no limit is provided
+     */
+    public int maxLength() {
+        var length = annotation(Length.class);
+        return length != null ? length.max() : -1;
+    }
 }

ap/src/main/java/org/geysermc/databaseutils/processor/info/EntityInfo.java

@@ -27,6 +27,18 @@ public ColumnInfo columnFor(CharSequence columnName) {
         return null;
     }
 
+    public List<ColumnInfo> columnsFor(CharSequence[] columnNames) {
+        var columns = new ArrayList<ColumnInfo>();
+        for (CharSequence columnName : columnNames) {
+            var column = columnFor(columnName);
+            if (column == null) {
+                throw new IllegalArgumentException("Column " + columnName + " not found");
+            }
+            columns.add(column);
+        }
+        return columns;
+    }
+
     public TypeMirror asType() {
         return type.asType();
     }

ap/src/main/java/org/geysermc/databaseutils/processor/info/IndexInfo.java

@@ -7,8 +7,22 @@
 
 import org.geysermc.databaseutils.meta.Index;
 
-public record IndexInfo(String name, CharSequence[] columns, boolean unique, Index.IndexDirection direction) {
-    public IndexInfo(String name, CharSequence[] columns, boolean unique) {
-        this(name, columns, unique, Index.IndexDirection.ASCENDING);
+public record IndexInfo(String name, CharSequence[] columns, IndexType type, Index.IndexDirection direction) {
+    public IndexInfo(String name, CharSequence[] columns, IndexType type) {
+        this(name, columns, type, Index.IndexDirection.ASCENDING);
+    }
+
+    public IndexInfo(String name, CharSequence[] columns, boolean unique, Index.IndexDirection direction) {
+        this(name, columns, unique ? IndexType.UNIQUE : IndexType.NORMAL, direction);
+    }
+
+    public boolean unique() {
+        return type == IndexType.UNIQUE || type == IndexType.PRIMARY;
+    }
+
+    public enum IndexType {
+        PRIMARY,
+        UNIQUE,
+        NORMAL
     }
 }