small code improvements/clean-ups

spring-ai-core/src/main/java/org/springframework/ai/vectorstore/SimpleVectorStoreContent.java

@@ -17,7 +17,6 @@
 package org.springframework.ai.vectorstore;
 
 import java.util.Arrays;
-import java.util.Collections;
 import java.util.HashMap;
 import java.util.Map;
 import java.util.Objects;
@@ -100,22 +99,10 @@ public SimpleVectorStoreContent(String id, String text, Map<String, Object> meta
 
 		this.id = id;
 		this.text = text;
-		this.metadata = Collections.unmodifiableMap(new HashMap<>(metadata));
+		this.metadata = Map.copyOf(metadata);
 		this.embedding = Arrays.copyOf(embedding, embedding.length);
 	}
 
-	/**
-	 * Creates a new instance with an updated embedding vector.
-	 * @param embedding the new embedding vector, must not be null
-	 * @return a new instance with the updated embedding
-	 * @throws IllegalArgumentException if embedding is null or empty
-	 */
-	public SimpleVectorStoreContent withEmbedding(float[] embedding) {
-		Assert.notNull(embedding, "embedding must not be null");
-		Assert.isTrue(embedding.length > 0, "embedding vector must not be empty");
-		return new SimpleVectorStoreContent(this.id, this.text, this.metadata, embedding);
-	}
-
 	public String getId() {
 		return this.id;
 	}

spring-ai-core/src/main/java/org/springframework/ai/vectorstore/filter/FilterExpressionBuilder.java

@@ -49,7 +49,8 @@
  * }</pre>
  *
  *
- * This builder DSL mimics the common https://www.baeldung.com/hibernate-criteria-queries
+ * This builder DSL mimics the common
+ * <a href="https://www.baeldung.com/hibernate-criteria-queries">Criteria Queries</a>
  * syntax.
  *
  * @author Christian Tzolov

spring-ai-core/src/main/java/org/springframework/ai/vectorstore/filter/FilterExpressionTextParser.java

@@ -21,7 +21,6 @@
 import java.util.Map;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.CopyOnWriteArrayList;
-import java.util.stream.Collectors;
 
 import org.antlr.v4.runtime.ANTLRErrorStrategy;
 import org.antlr.v4.runtime.BailErrorStrategy;
@@ -46,7 +45,7 @@
  *
  * The vector-store agnostic, filter expression language is defined by a formal ANTLR4
  * grammar (Filters.g4). The language looks and feels like a subset of the well known SQL
- * WHERE filter expressions. For example you can use the parser like this:
+ * WHERE filter expressions. For example, you can use the parser like this:
  *
  * <pre>{@code
  *
@@ -151,7 +150,7 @@ public Filter.Expression parse(String textFilterExpression) {
 			return filterExpression;
 		}
 		catch (ParseCancellationException e) {
-			var msg = this.errorListener.errorMessages.stream().collect(Collectors.joining());
+			var msg = String.join("", this.errorListener.errorMessages);
 			var rootCause = NestedExceptionUtils.getRootCause(e);
 			throw new FilterExpressionParseException(msg, rootCause);
 		}

spring-ai-core/src/main/java/org/springframework/ai/vectorstore/filter/converter/PineconeFilterExpressionConverter.java

@@ -22,7 +22,7 @@
 
 /**
  * Converts {@link Expression} into Pinecone metadata filter expression format.
- * (https://docs.pinecone.io/docs/metadata-filtering)
+ * (<a href="https://docs.pinecone.io/docs/metadata-filtering">Metadata filtering</a>)
  *
  * @author Christian Tzolov
  */
@@ -58,7 +58,7 @@ private String getOperationSymbol(Expression exp) {
 	@Override
 	protected void doKey(Key key, StringBuilder context) {
 		var identifier = (hasOuterQuotes(key.key())) ? removeOuterQuotes(key.key()) : key.key();
-		context.append("\"" + identifier + "\": ");
+		context.append("\"").append(identifier).append("\": ");
 	}
 
 }

spring-ai-core/src/main/java/org/springframework/ai/vectorstore/filter/converter/PrintFilterExpressionConverter.java

@@ -29,7 +29,7 @@ public class PrintFilterExpressionConverter extends AbstractFilterExpressionConv
 
 	public void doExpression(Expression expression, StringBuilder context) {
 		this.convertOperand(expression.left(), context);
-		context.append(" " + expression.type() + " ");
+		context.append(" ").append(expression.type()).append(" ");
 		this.convertOperand(expression.right(), context);
 
 	}