edit

Author: usfalami

src/main/java/org/usf/jquery/core/QueryContext.java

@@ -1,6 +1,7 @@
 package org.usf.jquery.core;
 
 import static java.util.Collections.emptyMap;
+import static java.util.Collections.unmodifiableMap;
 import static java.util.Objects.nonNull;
 import static java.util.Optional.ofNullable;
 import static java.util.stream.Collectors.joining;
@@ -148,18 +149,18 @@ public QueryContext withValue() {
 	}
 
 	public QueryContext subQuery(Map<DBView, QueryView> overView) {
-		return new QueryContext(schema, vPrefix + "_s", args, argTypes, new ArrayList<>(), overView);
+		return new QueryContext(schema, vPrefix + "_s", args, argTypes, new ArrayList<>(), unmodifiableMap(overView));
 	}
 
 	public static QueryContext addWithValue() {
 		return addWithValue(null, emptyMap()); //no args
 	}
 
 	public static QueryContext addWithValue(String schema, Map<DBView, QueryView> overView) {
-		return new QueryContext(schema, "v", null, null, new ArrayList<>(), overView); //no args
+		return new QueryContext(schema, "v", null, null, new ArrayList<>(), unmodifiableMap(overView)); //no args
 	}
 
 	public static QueryContext parameterized(String schema, Map<DBView, QueryView> overView) {
-		return new QueryContext(schema, "v", new ArrayList<>(), new ArrayList<>(), new ArrayList<>(), overView);
+		return new QueryContext(schema, "v", new ArrayList<>(), new ArrayList<>(), new ArrayList<>(), unmodifiableMap(overView));
 	}
 }

src/main/java/org/usf/jquery/core/WhenCase.java

@@ -1,6 +1,5 @@
 package org.usf.jquery.core;
 
-import static java.util.Objects.isNull;
 import static java.util.Objects.nonNull;
 import static org.usf.jquery.core.JDBCType.typeOf;
 import static org.usf.jquery.core.Nested.tryResolve;
@@ -33,11 +32,11 @@ public String sql(QueryContext qv, Object[] args) {
 
 	public String sql(QueryContext ctx) {
 		var sb = new StringBuilder(50);
-		sb = isNull(filter)
-				? sb.append("ELSE ")
-				: sb.append("WHEN ")
-				.append(filter.sql(ctx))
-				.append(" THEN ");
+		sb = nonNull(filter)
+				? sb.append("WHEN ")
+						.append(filter.sql(ctx))
+						.append(" THEN ")
+				: sb.append("ELSE ");
 		return sb.append(ctx.appendLiteral(value)).toString();
 	}
 

src/main/java/org/usf/jquery/web/ViewDecorator.java

@@ -5,19 +5,21 @@
 import static java.util.Map.entry;
 import static java.util.Objects.nonNull;
 import static java.util.Objects.requireNonNull;
+import static java.util.Optional.empty;
 import static java.util.Optional.ofNullable;
 import static java.util.stream.Collectors.toUnmodifiableMap;
 import static org.usf.jquery.core.SqlStringBuilder.quote;
 import static org.usf.jquery.core.Utils.isEmpty;
 import static org.usf.jquery.core.Validation.requireLegalVariable;
+import static org.usf.jquery.core.Validation.requireNArgs;
 import static org.usf.jquery.web.ColumnMetadata.columnMetadata;
 import static org.usf.jquery.web.ContextManager.currentContext;
 import static org.usf.jquery.web.NoSuchResourceException.undeclaredResouceException;
 import static org.usf.jquery.web.Parameters.COLUMN;
 import static org.usf.jquery.web.Parameters.COLUMN_DISTINCT;
-import static org.usf.jquery.web.Parameters.OFFSET;
 import static org.usf.jquery.web.Parameters.JOIN;
 import static org.usf.jquery.web.Parameters.LIMIT;
+import static org.usf.jquery.web.Parameters.OFFSET;
 import static org.usf.jquery.web.Parameters.ORDER;
 import static org.usf.jquery.web.Parameters.VIEW;
 import static org.usf.jquery.web.RequestParser.parseEntries;
@@ -188,17 +190,13 @@ default void parseFilters(QueryBuilder query, Map<String, String[]> parameters)
 
 	private static Optional<Integer> requirePositiveInt(String key, Map<String, String[]> parameters) {
 		if(parameters.containsKey(key)) {
-			var values = parameters.remove(key);
-			if(values.length == 1) {
-				var v = parseInt(values[0]);
-				if(v >= 0) {
-					return Optional.of(v);
-				}
-				throw new IllegalArgumentException(key + " cannot be negative");
+			var v = parseInt(requireNArgs(1, parameters.remove(key), ()-> key)[0]);
+			if(v >= 0) {
+				return Optional.of(v);
 			}
-			throw new IllegalArgumentException("too many value");
+			throw new IllegalArgumentException(key + " cannot be negative");
 		}
-		return Optional.empty();
+		return empty();
 	}
 
 	static Stream<String> flatParameters(String... arr) { //number local separator