diff --git a/datastructures-common/src/main/java/org/xbib/datastructures/common/StrictArrayMap.java b/datastructures-common/src/main/java/org/xbib/datastructures/common/StrictArrayMap.java
index d501a03..10a36f5 100644
--- a/datastructures-common/src/main/java/org/xbib/datastructures/common/StrictArrayMap.java
+++ b/datastructures-common/src/main/java/org/xbib/datastructures/common/StrictArrayMap.java
@@ -1,6 +1,5 @@
 package org.xbib.datastructures.common;
 
-import org.xbib.datastructures.common.StrictArraySet;
 import java.util.AbstractMap;
 import java.util.Collection;
 import java.util.Map;
@@ -77,7 +76,7 @@ public class StrictArrayMap<K, V> extends AbstractMap<K, V> implements Map<K, V>
     public V get(Object key) {
         for (int i = 0; i < keys.length; i++ ) {
             if (keys[i].equals(key)) {
-                return (V) values[i];
+                return values[i];
             }
         }
         return null;
@@ -113,10 +112,10 @@ public class StrictArrayMap<K, V> extends AbstractMap<K, V> implements Map<K, V>
         return new StrictArraySet<>(values);
     }
 
-    @SuppressWarnings("unchecked")
+    @SuppressWarnings({"unchecked", "rawtypes"})
     @Override
     public Set<Entry<K, V>> entrySet() {
-        Entry<K, V>[] entries = new Map.Entry[keys.length];
+        Map.Entry<K, V>[] entries = new Map.Entry[keys.length];
         for (int i = 0; i < keys.length; i++) {
             entries[i] = new EntryHolder<>(keys[i], values[i]);
         }
diff --git a/datastructures-common/src/main/java/org/xbib/datastructures/common/Utf8Util.java b/datastructures-common/src/main/java/org/xbib/datastructures/common/Utf8Util.java
index e848799..b6e75b2 100644
--- a/datastructures-common/src/main/java/org/xbib/datastructures/common/Utf8Util.java
+++ b/datastructures-common/src/main/java/org/xbib/datastructures/common/Utf8Util.java
@@ -2,6 +2,9 @@ package org.xbib.datastructures.common;
 
 public class Utf8Util {
 
+    public Utf8Util() {
+    }
+
     public static String decode(byte[] data, int offset, int length) {
         char[] chars = new char[length];
         int len = 0;
diff --git a/datastructures-json-noggit/src/test/java/org/xbib/datastructures/json/noggit/TestJSONParser.java b/datastructures-json-noggit/src/test/java/org/xbib/datastructures/json/noggit/TestJSONParser.java
index e95381b..4568470 100755
--- a/datastructures-json-noggit/src/test/java/org/xbib/datastructures/json/noggit/TestJSONParser.java
+++ b/datastructures-json-noggit/src/test/java/org/xbib/datastructures/json/noggit/TestJSONParser.java
@@ -247,10 +247,10 @@ public class TestJSONParser {
                                 ret += parser.getNumberChars().length();
                                 break;
                             case JSONParser.NUMBER:
-                                ret += parser.getDouble();
+                                ret = ret + (int)parser.getDouble();
                                 break;
                             case JSONParser.LONG:
-                                ret += parser.getLong();
+                                ret = ret + (int)parser.getLong();
                                 break;
                             default:
                                 ret += ev;
diff --git a/datastructures-json-noggit/src/test/java/org/xbib/datastructures/json/noggit/TestPerf.java b/datastructures-json-noggit/src/test/java/org/xbib/datastructures/json/noggit/TestPerf.java
index 760accc..2d93735 100755
--- a/datastructures-json-noggit/src/test/java/org/xbib/datastructures/json/noggit/TestPerf.java
+++ b/datastructures-json-noggit/src/test/java/org/xbib/datastructures/json/noggit/TestPerf.java
@@ -135,7 +135,7 @@ public class TestPerf {
                     ret += parser.getNumberChars().length();
                     break;
                 case JSONParser.NUMBER:
-                    ret += Double.doubleToRawLongBits(parser.getDouble());
+                    ret = ret + (int)Double.doubleToRawLongBits(parser.getDouble());
                     break;
                 case JSONParser.ARRAY_START:
                     ret += 13;
diff --git a/datastructures-json-tiny/src/main/java/org/xbib/datastructures/json/tiny/EmptyJsonListener.java b/datastructures-json-tiny/src/main/java/org/xbib/datastructures/json/tiny/EmptyJsonListener.java
index b008697..6425138 100644
--- a/datastructures-json-tiny/src/main/java/org/xbib/datastructures/json/tiny/EmptyJsonListener.java
+++ b/datastructures-json-tiny/src/main/java/org/xbib/datastructures/json/tiny/EmptyJsonListener.java
@@ -6,6 +6,9 @@ import java.util.Deque;
 
 public class EmptyJsonListener implements JsonResult {
 
+    public EmptyJsonListener() {
+    }
+
     @Override
     public void begin() {
     }
diff --git a/datastructures-json-tiny/src/main/java/org/xbib/datastructures/json/tiny/FastDoubleParser.java b/datastructures-json-tiny/src/main/java/org/xbib/datastructures/json/tiny/FastDoubleParser.java
index cf828fe..22838d4 100644
--- a/datastructures-json-tiny/src/main/java/org/xbib/datastructures/json/tiny/FastDoubleParser.java
+++ b/datastructures-json-tiny/src/main/java/org/xbib/datastructures/json/tiny/FastDoubleParser.java
@@ -156,7 +156,7 @@ public class FastDoubleParser {
             if (neg_exp) {
                 exp_number = -exp_number;
             }
-            exponent += exp_number;
+            exponent = exponent + (int)exp_number;
         }
         index = skipWhitespace(str, index, endIndex);
         if (index < endIndex
@@ -164,7 +164,7 @@ public class FastDoubleParser {
             throw newNumberFormatException(str);
         }
         final boolean isDigitsTruncated;
-        int skipCountInTruncatedDigits = 0;//counts +1 if we skipped over the decimal point
+        int skipCountInTruncatedDigits = 0;
         if (digitCount > 19) {
             digits = 0;
             for (index = indexOfFirstDigit; index < indexAfterDigits; index++) {
@@ -231,10 +231,7 @@ public class FastDoubleParser {
         if (index >= endIndex) {
             throw newNumberFormatException(str);
         }
-
-        // Parse digits
-        // ------------
-        long digits = 0;// digits is treated as an unsigned long
+        long digits = 0;
         int exponent = 0;
         final int indexOfFirstDigit = index;
         int virtualIndexOfPoint = -1;
@@ -242,10 +239,9 @@ public class FastDoubleParser {
         char ch = 0;
         for (; index < endIndex; index++) {
             ch = str.charAt(index);
-            // Table look up is faster than a sequence of if-else-branches.
             int hexValue = ch > 255 ? OTHER_CLASS : CHAR_TO_HEX_MAP[ch];
             if (hexValue >= 0) {
-                digits = (digits << 4) | hexValue;// This might overflow, we deal with it later.
+                digits = (digits << 4) | hexValue;
             } else if (hexValue == DECIMAL_POINT_CLASS) {
                 if (virtualIndexOfPoint != -1) {
                     throw newNumberFormatException(str);
@@ -263,9 +259,6 @@ public class FastDoubleParser {
             digitCount = indexAfterDigits - indexOfFirstDigit - 1;
             exponent = Math.min(virtualIndexOfPoint - index + 1, MINIMAL_EIGHT_DIGIT_INTEGER) * 4;
         }
-
-        // Parse exponent number
-        // ---------------------
         long exp_number = 0;
         final boolean hasExponent = (ch == 'p') || (ch == 'P');
         if (hasExponent) {
@@ -278,7 +271,6 @@ public class FastDoubleParser {
                 throw newNumberFormatException(str);
             }
             do {
-                // Guard against overflow of exp_number
                 if (exp_number < MINIMAL_EIGHT_DIGIT_INTEGER) {
                     exp_number = 10 * exp_number + ch - '0';
                 }
@@ -287,27 +279,20 @@ public class FastDoubleParser {
             if (neg_exp) {
                 exp_number = -exp_number;
             }
-            exponent += exp_number;
+            exponent = exponent + (int)exp_number;
         }
-
-        // Skip trailing whitespace
-        // ------------------------
         index = skipWhitespace(str, index, endIndex);
         if (index < endIndex
                 || digitCount == 0 && str.charAt(virtualIndexOfPoint) != '.'
                 || !hasExponent) {
             throw newNumberFormatException(str);
         }
-
-        // Re-parse digits in case of a potential overflow
-        // -----------------------------------------------
         final boolean isDigitsTruncated;
-        int skipCountInTruncatedDigits = 0;//counts +1 if we skipped over the decimal point
+        int skipCountInTruncatedDigits = 0;
         if (digitCount > 16) {
             digits = 0;
             for (index = indexOfFirstDigit; index < indexAfterDigits; index++) {
                 ch = str.charAt(index);
-                // Table look up is faster than a sequence of if-else-branches.
                 int hexValue = ch > 127 ? OTHER_CLASS : CHAR_TO_HEX_MAP[ch];
                 if (hexValue >= 0) {
                     if (Long.compareUnsigned(digits, MINIMAL_NINETEEN_DIGIT_INTEGER) < 0) {
diff --git a/datastructures-json-tiny/src/main/java/org/xbib/datastructures/json/tiny/ListNode.java b/datastructures-json-tiny/src/main/java/org/xbib/datastructures/json/tiny/ListNode.java
index b617fd2..cecb1a9 100644
--- a/datastructures-json-tiny/src/main/java/org/xbib/datastructures/json/tiny/ListNode.java
+++ b/datastructures-json-tiny/src/main/java/org/xbib/datastructures/json/tiny/ListNode.java
@@ -6,6 +6,9 @@ import java.util.List;
 
 public class ListNode extends TinyList.Builder<Node<?>> implements org.xbib.datastructures.api.ListNode {
 
+    public ListNode() {
+    }
+
     public boolean has(int i) {
         return i >= 0 && i < size() && get(i) == null;
     }
diff --git a/datastructures-json-tiny/src/main/java/org/xbib/datastructures/json/tiny/MapNode.java b/datastructures-json-tiny/src/main/java/org/xbib/datastructures/json/tiny/MapNode.java
index edb59b3..42e22e9 100644
--- a/datastructures-json-tiny/src/main/java/org/xbib/datastructures/json/tiny/MapNode.java
+++ b/datastructures-json-tiny/src/main/java/org/xbib/datastructures/json/tiny/MapNode.java
@@ -6,6 +6,9 @@ import java.util.Map;
 
 public class MapNode extends TinyMap.Builder<CharSequence, Node<?>> implements org.xbib.datastructures.api.MapNode {
 
+    public MapNode() {
+    }
+
     public boolean has(String name) {
         return containsKey(name);
     }
diff --git a/datastructures-json-tiny/src/main/java/org/xbib/datastructures/json/tiny/StandardJsonListener.java b/datastructures-json-tiny/src/main/java/org/xbib/datastructures/json/tiny/StandardJsonListener.java
index 5eeb537..264c2ef 100644
--- a/datastructures-json-tiny/src/main/java/org/xbib/datastructures/json/tiny/StandardJsonListener.java
+++ b/datastructures-json-tiny/src/main/java/org/xbib/datastructures/json/tiny/StandardJsonListener.java
@@ -17,6 +17,9 @@ public class StandardJsonListener implements JsonResult {
 
     private final ValueNode FALSE_NODE = new ValueNode(Boolean.FALSE);
 
+    public StandardJsonListener() {
+    }
+
     public Deque<Node<?>> getStack() {
         return stack;
     }
diff --git a/datastructures-json-tiny/src/main/java/org/xbib/datastructures/json/tiny/StandardListNode.java b/datastructures-json-tiny/src/main/java/org/xbib/datastructures/json/tiny/StandardListNode.java
index e581075..e16579b 100644
--- a/datastructures-json-tiny/src/main/java/org/xbib/datastructures/json/tiny/StandardListNode.java
+++ b/datastructures-json-tiny/src/main/java/org/xbib/datastructures/json/tiny/StandardListNode.java
@@ -8,6 +8,9 @@ import java.util.List;
 @SuppressWarnings("serial")
 public class StandardListNode extends ArrayList<Object> implements Node<List<Object>> {
 
+    public StandardListNode() {
+    }
+
     public boolean has(int i) {
         return i >= 0 && i < size() && get(i) == null;
     }
diff --git a/datastructures-json-tiny/src/main/java/org/xbib/datastructures/json/tiny/StandardMapNode.java b/datastructures-json-tiny/src/main/java/org/xbib/datastructures/json/tiny/StandardMapNode.java
index 4e37b6c..df77817 100644
--- a/datastructures-json-tiny/src/main/java/org/xbib/datastructures/json/tiny/StandardMapNode.java
+++ b/datastructures-json-tiny/src/main/java/org/xbib/datastructures/json/tiny/StandardMapNode.java
@@ -8,6 +8,9 @@ import java.util.Map;
 @SuppressWarnings("serial")
 public class StandardMapNode extends LinkedHashMap<CharSequence, Object> implements Node<Map<CharSequence, Object>> {
 
+    public StandardMapNode() {
+    }
+
     public boolean has(String name) {
         return containsKey(name);
     }
diff --git a/datastructures-json-tiny/src/main/java/org/xbib/datastructures/json/tiny/StreamParser.java b/datastructures-json-tiny/src/main/java/org/xbib/datastructures/json/tiny/StreamParser.java
index 8e80960..0c13ad0 100644
--- a/datastructures-json-tiny/src/main/java/org/xbib/datastructures/json/tiny/StreamParser.java
+++ b/datastructures-json-tiny/src/main/java/org/xbib/datastructures/json/tiny/StreamParser.java
@@ -271,7 +271,7 @@ public class StreamParser implements Parser {
 
     private void expectChar(char expected) throws JsonException {
         if (ch != expected) {
-            throw new JsonException("expected char " + (char)expected + " but got " + (char)ch);
+            throw new JsonException("expected char " + expected + " but got " + (char)ch);
         }
     }
 
diff --git a/datastructures-json-tiny/src/main/java/org/xbib/datastructures/json/tiny/TinyJsonListener.java b/datastructures-json-tiny/src/main/java/org/xbib/datastructures/json/tiny/TinyJsonListener.java
index 445964a..89fe2c4 100644
--- a/datastructures-json-tiny/src/main/java/org/xbib/datastructures/json/tiny/TinyJsonListener.java
+++ b/datastructures-json-tiny/src/main/java/org/xbib/datastructures/json/tiny/TinyJsonListener.java
@@ -17,6 +17,9 @@ public class TinyJsonListener implements JsonResult {
 
     private final ValueNode FALSE_NODE = new ValueNode(Boolean.FALSE);
 
+    public TinyJsonListener() {
+    }
+
     @Override
     public Node<?> getResult() {
         return node;
diff --git a/datastructures-tiny/src/main/java/org/xbib/datastructures/tiny/IndexedListBase.java b/datastructures-tiny/src/main/java/org/xbib/datastructures/tiny/IndexedListBase.java
index 04d9400..506a05a 100644
--- a/datastructures-tiny/src/main/java/org/xbib/datastructures/tiny/IndexedListBase.java
+++ b/datastructures-tiny/src/main/java/org/xbib/datastructures/tiny/IndexedListBase.java
@@ -8,6 +8,9 @@ import java.util.function.Consumer;
 
 public abstract class IndexedListBase<T> extends IndexedCollectionBase<T> implements IndexedList<T> {
 
+    public IndexedListBase() {
+    }
+
     @Override
     public boolean addAll(int index, Collection<? extends T> collection) {
         boolean added = false;
diff --git a/datastructures-tiny/src/main/java/org/xbib/datastructures/tiny/IndexedMapBase.java b/datastructures-tiny/src/main/java/org/xbib/datastructures/tiny/IndexedMapBase.java
index f041870..e94a7a7 100644
--- a/datastructures-tiny/src/main/java/org/xbib/datastructures/tiny/IndexedMapBase.java
+++ b/datastructures-tiny/src/main/java/org/xbib/datastructures/tiny/IndexedMapBase.java
@@ -6,8 +6,12 @@ import java.util.Objects;
 import java.util.function.BiConsumer;
 
 public abstract class IndexedMapBase<K, V> implements IndexedMap<K, V> {
+
     private static final Object SENTINEL = new Object();
 
+    public IndexedMapBase() {
+    }
+
     @Override
     public V getOrDefault(Object key, V defaultValue) {
         int index = getIndex(key);
diff --git a/datastructures-tiny/src/main/java/org/xbib/datastructures/tiny/IndexedSetBase.java b/datastructures-tiny/src/main/java/org/xbib/datastructures/tiny/IndexedSetBase.java
index dd97f1e..4bdd466 100644
--- a/datastructures-tiny/src/main/java/org/xbib/datastructures/tiny/IndexedSetBase.java
+++ b/datastructures-tiny/src/main/java/org/xbib/datastructures/tiny/IndexedSetBase.java
@@ -5,6 +5,9 @@ import java.util.Set;
 
 public abstract class IndexedSetBase<T> extends IndexedCollectionBase<T> implements IndexedSet<T> {
 
+    public IndexedSetBase() {
+    }
+
     @Override
     public boolean equals(Object o) {
         if (this == o) {
diff --git a/datastructures-tiny/src/main/java/org/xbib/datastructures/tiny/Preconditions.java b/datastructures-tiny/src/main/java/org/xbib/datastructures/tiny/Preconditions.java
index c534bdd..817d825 100644
--- a/datastructures-tiny/src/main/java/org/xbib/datastructures/tiny/Preconditions.java
+++ b/datastructures-tiny/src/main/java/org/xbib/datastructures/tiny/Preconditions.java
@@ -2,6 +2,9 @@ package org.xbib.datastructures.tiny;
 
 public abstract class Preconditions {
 
+    public Preconditions() {
+    }
+
     public static void checkArgument(boolean expression, String errorMessage) {
         if (!expression) {
             throw new IllegalArgumentException(errorMessage);
diff --git a/datastructures-tiny/src/main/java/org/xbib/datastructures/tiny/TinySet.java b/datastructures-tiny/src/main/java/org/xbib/datastructures/tiny/TinySet.java
index 43ca743..ee8c5c3 100644
--- a/datastructures-tiny/src/main/java/org/xbib/datastructures/tiny/TinySet.java
+++ b/datastructures-tiny/src/main/java/org/xbib/datastructures/tiny/TinySet.java
@@ -5,6 +5,9 @@ import java.util.Objects;
 
 public abstract class TinySet<T> extends IndexedSetBase<T> {
 
+    public TinySet() {
+    }
+
     public static int tableSize(int length) {
         return Integer.highestOneBit(length * 2 - 1) * 2;
     }
diff --git a/gradle.properties b/gradle.properties
index 2ac09bf..a5fbade 100644
--- a/gradle.properties
+++ b/gradle.properties
@@ -1,5 +1,5 @@
 group = org.xbib
 name = datastructures
-version = 1.0.1
+version = 2.0.0
 
 org.gradle.warning.mode = ALL
diff --git a/gradle/compile/java.gradle b/gradle/compile/java.gradle
index de7e0b3..6e70802 100644
--- a/gradle/compile/java.gradle
+++ b/gradle/compile/java.gradle
@@ -6,13 +6,13 @@ java {
 }
 
 compileJava {
-    sourceCompatibility = JavaVersion.VERSION_11
-    targetCompatibility = JavaVersion.VERSION_11
+    sourceCompatibility = JavaVersion.VERSION_17
+    targetCompatibility = JavaVersion.VERSION_17
 }
 
 compileTestJava {
-    sourceCompatibility = JavaVersion.VERSION_11
-    targetCompatibility = JavaVersion.VERSION_11
+    sourceCompatibility = JavaVersion.VERSION_17
+    targetCompatibility = JavaVersion.VERSION_17
 }
 
 jar {
@@ -38,10 +38,11 @@ artifacts {
 }
 
 tasks.withType(JavaCompile) {
-  // commented out mostly because of jmh generated code
-    options.compilerArgs << '-Xlint:all'
+    options.compilerArgs.add('-Xlint:all')
+    options.encoding = 'UTF-8'
 }
 
-javadoc {
+tasks.withType(Javadoc) {
     options.addStringOption('Xdoclint:none', '-quiet')
+    options.encoding = 'UTF-8'
 }