Stack => Deque and gc unused ConfigFileFormat

8 files changed, 140 insertions, 687 deletions

diff --git a/config/src/main/java/com/yahoo/vespa/config/ConfigFileFormat.java b/config/src/main/java/com/yahoo/vespa/config/ConfigFileFormat.java
deleted file mode 100644
index 16a3ef3371d..00000000000
--- a/config/src/main/java/com/yahoo/vespa/config/ConfigFileFormat.java
+++ /dev/null
@@ -1,228 +0,0 @@
-// Copyright Yahoo. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
-package com.yahoo.vespa.config;
-
-import com.yahoo.config.codegen.CNode;
-import com.yahoo.config.codegen.InnerCNode;
-import com.yahoo.config.codegen.LeafCNode;
-import com.yahoo.slime.*;
-import com.yahoo.text.Utf8;
-import com.yahoo.vespa.config.util.ConfigUtils;
-
-import java.io.*;
-import java.util.Stack;
-
-/**
- * @author Ulf Lilleengen
- */
-public class ConfigFileFormat implements SlimeFormat, ObjectTraverser {
-
-    private final InnerCNode root;
-    private DataOutputStream out = null;
-    private Stack<Node> nodeStack;
-
-    public ConfigFileFormat(InnerCNode root) {
-        this.root = root;
-        this.nodeStack = new Stack<>();
-    }
-
-    private void printPrefix() throws IOException {
-        for (Node node : nodeStack) {
-            CNode cnode = node.node;
-            if (cnode != root) {
-                encodeString(cnode.getName());
-                if (cnode.isArray) {
-                    encodeString("[" + node.arrayIndex + "]");
-                    if (!(cnode instanceof LeafCNode)) {
-                        encodeString(".");
-                    }
-                } else if (cnode.isMap) {
-                    encodeString("{\"" + node.mapKey + "\"}");
-                    if (!(cnode instanceof LeafCNode)) {
-                        encodeString(".");
-                    }
-                } else if (cnode instanceof LeafCNode) {
-                    encodeString("");
-                } else {
-                    encodeString(".");
-                }
-            }
-        }
-        encodeString(" ");
-    }
-
-    private void encode(Inspector inspector, CNode node) throws IOException {
-        switch (inspector.type()) {
-            case BOOL:
-                encodeValue(String.valueOf(inspector.asBool()), (LeafCNode) node);
-                return;
-            case LONG:
-                encodeValue(String.valueOf(inspector.asLong()), (LeafCNode) node);
-                return;
-            case DOUBLE:
-                encodeValue(String.valueOf(inspector.asDouble()), (LeafCNode) node);
-                return;
-            case STRING:
-                encodeValue(inspector.asString(), (LeafCNode) node);
-                return;
-            case ARRAY:
-                encodeArray(inspector, node);
-                return;
-            case OBJECT:
-                if (node.isMap) {
-                    encodeMap(inspector, node);
-                } else {
-                    encodeObject(inspector, node);
-                }
-                return;
-            case NIX:
-            case DATA:
-                throw new IllegalArgumentException("Illegal config format supplied. Unknown type for field '" + node.getName() + "'");
-        }
-        throw new RuntimeException("Should not be reached");
-    }
-
-    private void encodeMap(Inspector inspector, final CNode node) {
-        inspector.traverse(new ObjectTraverser() {
-            @Override
-            public void field(String name, Inspector inspector) {
-                try {
-                    nodeStack.push(new Node(node, -1, name));
-                    if (inspector.type().equals(Type.OBJECT)) {
-                        encodeObject(inspector, node);
-                    } else {
-                        encode(inspector, node);
-                    }
-                    nodeStack.pop();
-                } catch (IOException e) {
-                    throw new RuntimeException(e);
-                }
-            }
-        });
-    }
-
-    private void encodeArray(Inspector inspector, final CNode node) {
-        inspector.traverse(new ArrayTraverser() {
-            @Override
-            public void entry(int idx, Inspector inspector) {
-                try {
-                    nodeStack.push(new Node(node, idx, ""));
-                    encode(inspector, node);
-                    nodeStack.pop();
-                } catch (IOException e) {
-                    throw new RuntimeException(e);
-                }
-            }
-        });
-
-    }
-
-    private void encodeObject(Inspector inspector, CNode node) {
-        if (!node.isArray && !node.isMap) {
-            nodeStack.push(new Node(node));
-            inspector.traverse(this);
-            nodeStack.pop();
-        } else {
-            inspector.traverse(this);
-        }
-    }
-
-    private void encodeValue(String value, LeafCNode node) throws IOException {
-        printPrefix();
-        try {
-            if (node instanceof LeafCNode.StringLeaf) {
-                encodeStringQuoted(value);
-            } else if (node instanceof LeafCNode.IntegerLeaf) {
-                //Integer.parseInt(value);
-                encodeString(value);
-            } else if (node instanceof LeafCNode.LongLeaf) {
-                //Long.parseLong(value);
-                encodeString(value);
-            } else if (node instanceof LeafCNode.DoubleLeaf) {
-                //Double.parseDouble(value);
-                encodeString(value);
-            } else if (node instanceof LeafCNode.BooleanLeaf) {
-                encodeString(String.valueOf(Boolean.parseBoolean(value)));
-            } else if (node instanceof LeafCNode.EnumLeaf) {
-                // LeafCNode.EnumLeaf enumNode = (LeafCNode.EnumLeaf) node;
-                // TODO: Reenable this when we can return illegal config id.
-                // checkLegalEnumValue(enumNode, value);
-                encodeString(value);
-            } else {
-                encodeStringQuoted(value);
-            }
-            encodeString("\n");
-        } catch (Exception e) {
-            throw new IllegalArgumentException("Unable to serialize field '" + node.getFullName() + "': ", e);
-        }
-    }
-
-    private void checkLegalEnumValue(LeafCNode.EnumLeaf enumNode, String value) {
-        boolean found = false;
-        for (String legalVal : enumNode.getLegalValues()) {
-            if (legalVal.equals(value)) {
-                found = true;
-            }
-        }
-        if (!found)
-            throw new IllegalArgumentException("Illegal enum value '" + value + "'");
-    }
-
-    private void encodeStringQuoted(String s) throws IOException {
-        encodeString("\"" + escapeString(s) + "\"");
-    }
-
-    private String escapeString(String s) {
-        return ConfigUtils.escapeConfigFormatValue(s);
-    }
-
-    private void encodeString(String s) throws IOException {
-        out.write(Utf8.toBytes(s));
-    }
-
-    @Override
-    public void encode(OutputStream os, Slime slime) throws IOException {
-        encode(os, slime.get());
-    }
-
-    private void encode(OutputStream os, Inspector inspector) throws IOException {
-        this.out = new DataOutputStream(os);
-        this.nodeStack = new Stack<>();
-        nodeStack.push(new Node(root));
-        encode(inspector, root);
-    }
-
-    @Override
-    public void field(String fieldName,  Inspector inspector) {
-        try {
-            Node parent = nodeStack.peek();
-            CNode child = parent.node.getChild(fieldName);
-            if (child == null) {
-                return; // Skip this field to optimistic
-            }
-            if (!child.isArray && !child.isMap && child instanceof LeafCNode) {
-                nodeStack.push(new Node(child));
-                encode(inspector, child);
-                nodeStack.pop();
-            } else {
-                encode(inspector, child);
-            }
-        } catch (IOException e) {
-            throw new RuntimeException(e);
-        }
-    }
-
-    private class Node {
-        final int arrayIndex;
-        final String mapKey;
-        final CNode node;
-        Node(CNode node, int arrayIndex, String mapKey) {
-            this.node = node;
-            this.arrayIndex = arrayIndex;
-            this.mapKey = mapKey;
-        }
-
-        Node(CNode node) {
-            this(node, -1, "");
-        }
-    }
-}
diff --git a/config/src/main/java/com/yahoo/vespa/config/ConfigPayloadApplier.java b/config/src/main/java/com/yahoo/vespa/config/ConfigPayloadApplier.java
index 3705c167960..e86b13b2c98 100644
--- a/config/src/main/java/com/yahoo/vespa/config/ConfigPayloadApplier.java
+++ b/config/src/main/java/com/yahoo/vespa/config/ConfigPayloadApplier.java
@@ -8,7 +8,6 @@ import com.yahoo.config.ModelReference;
 import com.yahoo.config.UrlReference;
 import com.yahoo.slime.ArrayTraverser;
 import com.yahoo.slime.Inspector;
-import com.yahoo.slime.ObjectTraverser;
 import com.yahoo.slime.Type;
 import java.io.File;
 import java.lang.reflect.Constructor;
@@ -17,11 +16,12 @@ import java.lang.reflect.InvocationTargetException;
 import java.lang.reflect.Method;
 import java.lang.reflect.ParameterizedType;
 import java.nio.file.Path;
+import java.util.ArrayDeque;
+import java.util.Deque;
 import java.util.HashMap;
 import java.util.HashSet;
 import java.util.Map;
 import java.util.Set;
-import java.util.Stack;
 import java.util.logging.Logger;
 
 import static java.util.logging.Level.INFO;
@@ -42,7 +42,7 @@ public class ConfigPayloadApplier<T extends ConfigInstance.Builder> {
     private final ConfigInstance.Builder rootBuilder;
     private final ConfigTransformer.PathAcquirer pathAcquirer;
     private final UrlDownloader urlDownloader;
-    private final Stack<NamedBuilder> stack = new Stack<>();
+    private final Deque<NamedBuilder> stack = new ArrayDeque<>();
 
     public ConfigPayloadApplier(T builder) {
         this(builder, new IdentityPathAcquirer(), null);
@@ -67,27 +67,17 @@ public class ConfigPayloadApplier<T extends ConfigInstance.Builder> {
 
     private void handleValue(Inspector inspector) {
         switch (inspector.type()) {
-            case NIX:
-            case BOOL:
-            case LONG:
-            case DOUBLE:
-            case STRING:
-            case DATA:
-                handleLeafValue(inspector);
-                break;
-            case ARRAY:
-                handleARRAY(inspector);
-                break;
-            case OBJECT:
-                handleOBJECT(inspector);
-                break;
-            default:
+            case NIX, BOOL, LONG, DOUBLE, STRING, DATA -> handleLeafValue(inspector);
+            case ARRAY -> handleARRAY(inspector);
+            case OBJECT -> handleOBJECT(inspector);
+            default -> {
                 assert false : "Should not be reached";
+            }
         }
     }
 
     private void handleARRAY(Inspector inspector) {
-        inspector.traverse((ArrayTraverser)(int index, Inspector value) -> handleArrayEntry(index, value));
+        inspector.traverse((ArrayTraverser) this::handleArrayEntry);
     }
 
     private void handleArrayEntry(int idx, Inspector inspector) {
@@ -108,11 +98,11 @@ public class ConfigPayloadApplier<T extends ConfigInstance.Builder> {
     }
 
     private void handleOBJECT(Inspector inspector) {
-        inspector.traverse((String name, Inspector value) -> handleObjectEntry(name, value));
+        inspector.traverse(this::handleObjectEntry);
         NamedBuilder builder = stack.pop();
 
         // Need to set e.g struct(Struct.Builder) here
-        if ( ! stack.empty()) {
+        if ( ! stack.isEmpty()) {
             try {
                 invokeSetter(stack.peek().builder, builder.peekName(), builder.builder);
             } catch (Exception e) {
@@ -165,7 +155,7 @@ public class ConfigPayloadApplier<T extends ConfigInstance.Builder> {
             throw new RuntimeException("Missing map builder (this should never happen): " + stack.peek());
         setMapLeafValue(name, builder.builder());
         stack.push(builder);
-        inspector.traverse((ObjectTraverser) (key, value) -> handleObjectEntry(key, value));
+        inspector.traverse(this::handleObjectEntry);
         stack.pop();
     }
 
@@ -296,18 +286,24 @@ public class ConfigPayloadApplier<T extends ConfigInstance.Builder> {
 
     private Object getValueFromInspector(Inspector inspector) {
         switch (inspector.type()) {
-            case STRING:
+            case STRING -> {
                 return inspector.asString();
-            case LONG:
+            }
+            case LONG -> {
                 return String.valueOf(inspector.asLong());
-            case DOUBLE:
+            }
+            case DOUBLE -> {
                 return String.valueOf(inspector.asDouble());
-            case NIX:
+            }
+            case NIX -> {
                 return null;
-            case BOOL:
+            }
+            case BOOL -> {
                 return String.valueOf(inspector.asBool());
-            case DATA:
+            }
+            case DATA -> {
                 return String.valueOf(inspector.asData());
+            }
         }
         throw new IllegalArgumentException("Unhandled type " + inspector.type());
     }
@@ -372,7 +368,7 @@ public class ConfigPayloadApplier<T extends ConfigInstance.Builder> {
         return name.substring(0, 1).toUpperCase() + name.substring(1);
     }
 
-    private Constructor<?> lookupBuilderForStruct(String structName, String name, Class<?> currentClass) {
+    private Constructor<?> lookupBuilderForStruct(String structName, Class<?> currentClass) {
         String currentClassName = currentClass.getName();
         Class<?> structClass = getInnerClass(currentClass, currentClassName + "$" + structName);
         if (structClass == null) {
@@ -420,7 +416,7 @@ public class ConfigPayloadApplier<T extends ConfigInstance.Builder> {
         String key = constructorCacheKey(structName, name, currentClass);
         Constructor<?> constructor = constructorCache.get(key);
         if (constructor == null) {
-            constructor = lookupBuilderForStruct(structName, name, currentClass);
+            constructor = lookupBuilderForStruct(structName, currentClass);
             if (constructor == null) return null;
             constructorCache.put(key, constructor);
         }
@@ -437,7 +433,7 @@ public class ConfigPayloadApplier<T extends ConfigInstance.Builder> {
     private static class NamedBuilder {
 
         private final ConfigBuilder builder;
-        private final Stack<String> names = new Stack<>(); // if empty, the builder is the root builder
+        private final Deque<String> names = new ArrayDeque<>(); // if empty, the builder is the root builder
 
         NamedBuilder(ConfigBuilder builder) {
             this.builder = builder;
@@ -456,7 +452,7 @@ public class ConfigPayloadApplier<T extends ConfigInstance.Builder> {
             return names.peek();
         }
 
-        Stack<String> nameStack() {
+        Deque<String> nameStack() {
             return names;
         }
 
diff --git a/config/src/main/java/com/yahoo/vespa/config/protocol/SlimeTraceSerializer.java b/config/src/main/java/com/yahoo/vespa/config/protocol/SlimeTraceSerializer.java
index 875033f1ffa..5193ecddc82 100644
--- a/config/src/main/java/com/yahoo/vespa/config/protocol/SlimeTraceSerializer.java
+++ b/config/src/main/java/com/yahoo/vespa/config/protocol/SlimeTraceSerializer.java
@@ -5,8 +5,9 @@ import com.yahoo.slime.Cursor;
 import com.yahoo.yolean.trace.TraceNode;
 import com.yahoo.yolean.trace.TraceVisitor;
 
+import java.util.ArrayDeque;
+import java.util.Deque;
 import java.util.Iterator;
-import java.util.Stack;
 
 /**
  * Serialize a {@link TraceNode} to {@link com.yahoo.slime.Slime}.
@@ -17,7 +18,7 @@ public class SlimeTraceSerializer extends TraceVisitor {
     static final String TIMESTAMP = "timestamp";
     static final String PAYLOAD = "payload";
     static final String CHILDREN = "children";
-    final Stack<Cursor> cursors = new Stack<>();
+    final Deque<Cursor> cursors = new ArrayDeque<>();
 
     public SlimeTraceSerializer(Cursor cursor) {
         cursors.push(cursor);
diff --git a/config/src/test/java/com/yahoo/vespa/config/ConfigFileFormatterTest.java b/config/src/test/java/com/yahoo/vespa/config/ConfigFileFormatterTest.java
deleted file mode 100644
index ab07b669bd0..00000000000
--- a/config/src/test/java/com/yahoo/vespa/config/ConfigFileFormatterTest.java
+++ /dev/null
@@ -1,338 +0,0 @@
-// Copyright Yahoo. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
-package com.yahoo.vespa.config;
-
-import com.yahoo.foo.ArraytypesConfig;
-import com.yahoo.foo.SimpletypesConfig;
-import com.yahoo.foo.StructtypesConfig;
-import com.yahoo.config.codegen.DefParser;
-import com.yahoo.config.codegen.InnerCNode;
-import com.yahoo.foo.MaptypesConfig;
-import com.yahoo.slime.Cursor;
-import com.yahoo.slime.Slime;
-import com.yahoo.text.StringUtilities;
-import com.yahoo.text.Utf8;
-import org.junit.Test;
-import org.junit.Ignore;
-
-import java.io.ByteArrayOutputStream;
-import java.io.IOException;
-import java.io.StringReader;
-import java.nio.charset.StandardCharsets;
-
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertTrue;
-
-/**
- * @author Ulf Lilleengen
- */
-public class ConfigFileFormatterTest {
-
-    private final String expected_simpletypes = "stringval \"foo\"\n" +
-            "intval 324234\n"  +
-            "longval 324\n"  +
-            "doubleval 3.455\n" +
-            "enumval VAL2\n" +
-            "boolval true\n";
-
-    @Test
-    public void require_that_basic_formatting_is_correct() throws IOException {
-        Slime slime = new Slime();
-        Cursor root = slime.setObject();
-        root.setString("stringval", "foo");
-        root.setString("intval", "324234");
-        root.setString("longval", "324");
-        root.setString("doubleval", "3.455");
-        root.setString("enumval", "VAL2");
-        root.setString("boolval", "true");
-
-        assertConfigFormat(slime, expected_simpletypes);
-    }
-
-    @Test
-    public void require_that_basic_formatting_is_correct_with_types() throws IOException {
-        Slime slime = new Slime();
-        Cursor root = slime.setObject();
-        root.setString("stringval", "foo");
-        root.setLong("intval", 324234);
-        root.setLong("longval", 324);
-        root.setDouble("doubleval", 3.455);
-        root.setString("enumval", "VAL2");
-        root.setBool("boolval", true);
-
-        assertConfigFormat(slime, expected_simpletypes);
-    }
-
-    private void assertConfigFormat(Slime slime, String expected_simpletypes) throws IOException {
-        ByteArrayOutputStream baos = new ByteArrayOutputStream();
-        InnerCNode def = new DefParser("simpletypes", new StringReader(StringUtilities.implode(SimpletypesConfig.CONFIG_DEF_SCHEMA, "\n"))).getTree();
-        new ConfigFileFormat(def).encode(baos, slime);
-        assertEquals(expected_simpletypes, baos.toString());
-    }
-
-    @Test
-    public void require_that_field_not_found_is_ignored() throws IOException {
-        Slime slime = new Slime();
-        Cursor root = slime.setObject();
-        root.setString("nosuchfield", "bar");
-        InnerCNode def = new DefParser("simpletypes", new StringReader(StringUtilities.implode(SimpletypesConfig.CONFIG_DEF_SCHEMA, "\n"))).getTree();
-        ByteArrayOutputStream baos = new ByteArrayOutputStream();
-        new ConfigFileFormat(def).encode(baos, slime);
-        assertTrue(baos.toString().isEmpty());
-    }
-
-    // TODO: Reenable this when we can reenable typechecking.
-    @Ignore
-    @Test(expected = IllegalArgumentException.class)
-    public void require_that_illegal_int_throws_exception() throws IOException {
-        Slime slime = new Slime();
-        Cursor root = slime.setObject();
-        root.setString("intval", "invalid");
-        InnerCNode def = new DefParser("simpletypes", new StringReader(StringUtilities.implode(SimpletypesConfig.CONFIG_DEF_SCHEMA, "\n"))).getTree();
-        new ConfigFileFormat(def).encode(new ByteArrayOutputStream(), slime);
-    }
-
-    // TODO: Reenable this when we can reenable typechecking.
-    @Ignore
-    @Test(expected = IllegalArgumentException.class)
-    public void require_that_illegal_long_throws_exception() throws IOException {
-        Slime slime = new Slime();
-        Cursor root = slime.setObject();
-        root.setString("longval", "invalid");
-        InnerCNode def = new DefParser("simpletypes", new StringReader(StringUtilities.implode(SimpletypesConfig.CONFIG_DEF_SCHEMA, "\n"))).getTree();
-        new ConfigFileFormat(def).encode(new ByteArrayOutputStream(), slime);
-    }
-
-    // TODO: Reenable this when we can reenable typechecking.
-    @Ignore
-    @Test(expected = IllegalArgumentException.class)
-    public void require_that_illegal_double_throws_exception() throws IOException {
-        Slime slime = new Slime();
-        Cursor root = slime.setObject();
-        root.setString("doubleval", "invalid");
-        InnerCNode def = new DefParser("simpletypes", new StringReader(StringUtilities.implode(SimpletypesConfig.CONFIG_DEF_SCHEMA, "\n"))).getTree();
-        new ConfigFileFormat(def).encode(new ByteArrayOutputStream(), slime);
-    }
-
-    @Test
-    public void require_that_illegal_boolean_becomes_false() throws IOException {
-        Slime slime = new Slime();
-        Cursor root = slime.setObject();
-        root.setString("boolval", "invalid");
-        InnerCNode def = new DefParser("simpletypes", new StringReader(StringUtilities.implode(SimpletypesConfig.CONFIG_DEF_SCHEMA, "\n"))).getTree();
-        ByteArrayOutputStream baos = new ByteArrayOutputStream();
-        new ConfigFileFormat(def).encode(baos, slime);
-        assertEquals("boolval false\n", baos.toString());
-    }
-
-    // TODO: Remove this when we can reenable typechecking.
-    @Test
-    public void require_that_types_are_not_checked() throws IOException {
-        Slime slime = new Slime();
-        Cursor root = slime.setObject();
-        root.setString("enumval", "null");
-        root.setString("intval", "null");
-        root.setString("longval", "null");
-        root.setString("boolval", "null");
-        root.setString("doubleval", "null");
-        InnerCNode def = new DefParser("simpletypes", new StringReader(StringUtilities.implode(SimpletypesConfig.CONFIG_DEF_SCHEMA, "\n"))).getTree();
-        ByteArrayOutputStream baos = new ByteArrayOutputStream();
-        new ConfigFileFormat(def).encode(baos, slime);
-        assertEquals("enumval null\nintval null\nlongval null\nboolval false\ndoubleval null\n",
-                baos.toString(StandardCharsets.UTF_8));
-    }
-
-    // TODO: Reenable this when we can reenable typechecking.
-    @Ignore
-    @Test(expected = IllegalArgumentException.class)
-    public void require_that_illegal_enum_throws_exception() throws IOException {
-        Slime slime = new Slime();
-        Cursor root = slime.setObject();
-        root.setString("enumval", "invalid");
-        InnerCNode def = new DefParser("simpletypes", new StringReader(StringUtilities.implode(SimpletypesConfig.CONFIG_DEF_SCHEMA, "\n"))).getTree();
-        new ConfigFileFormat(def).encode(new ByteArrayOutputStream(), slime);
-    }
-
-    @Test
-    public void require_that_strings_are_encoded() throws IOException {
-        Slime slime = new Slime();
-        Cursor root = slime.setObject();
-        String value = "\u7d22";
-        root.setString("stringval", value);
-        ByteArrayOutputStream baos = new ByteArrayOutputStream();
-        InnerCNode def = new DefParser("simpletypes", new StringReader(StringUtilities.implode(SimpletypesConfig.CONFIG_DEF_SCHEMA, "\n"))).getTree();
-        new ConfigFileFormat(def).encode(baos, slime);
-        assertEquals("stringval \"" + value + "\"\n", baos.toString(StandardCharsets.UTF_8));
-    }
-
-    @Test
-    public void require_that_array_formatting_is_correct() throws IOException {
-        Slime slime = new Slime();
-        Cursor root = slime.setObject();
-        Cursor boolarr = root.setArray("boolarr");
-        boolarr.addString("true");
-        boolarr.addString("false");
-        Cursor doublearr = root.setArray("doublearr");
-        doublearr.addString("3.14");
-        doublearr.addString("1.414");
-        Cursor enumarr = root.setArray("enumarr");
-        enumarr.addString("VAL1");
-        enumarr.addString("VAL2");
-        Cursor intarr = root.setArray("intarr");
-        intarr.addString("3");
-        intarr.addString("5");
-        Cursor longarr = root.setArray("longarr");
-        longarr.addString("55");
-        longarr.addString("66");
-        Cursor stringarr = root.setArray("stringarr");
-        stringarr.addString("foo");
-        stringarr.addString("bar");
-
-        ByteArrayOutputStream baos = new ByteArrayOutputStream();
-        InnerCNode def = new DefParser("arraytypes", new StringReader(StringUtilities.implode(ArraytypesConfig.CONFIG_DEF_SCHEMA, "\n"))).getTree();
-        new ConfigFileFormat(def).encode(baos, slime);
-        assertEquals(
-                "boolarr[0] true\n" +
-                "boolarr[1] false\n" +
-                "doublearr[0] 3.14\n" +
-                "doublearr[1] 1.414\n" +
-                "enumarr[0] VAL1\n" +
-                "enumarr[1] VAL2\n" +
-                "intarr[0] 3\n" +
-                "intarr[1] 5\n" +
-                "longarr[0] 55\n" +
-                "longarr[1] 66\n" +
-                "stringarr[0] \"foo\"\n" +
-                "stringarr[1] \"bar\"\n",
-                baos.toString());
-    }
-
-    @Test
-    public void require_that_map_formatting_is_correct() throws IOException {
-        Slime slime = new Slime();
-        Cursor root = slime.setObject();
-        Cursor boolval = root.setObject("boolmap");
-        boolval.setString("foo", "true");
-        boolval.setString("bar", "false");
-        root.setObject("intmap").setString("foo", "1234");
-        root.setObject("longmap").setString("foo", "12345");
-        root.setObject("doublemap").setString("foo", "3.14");
-        root.setObject("stringmap").setString("foo", "bar");
-        root.setObject("innermap").setObject("bar").setString("foo", "1234");
-        root.setObject("nestedmap").setObject("baz").setObject("inner").setString("foo", "1234");
-
-        ByteArrayOutputStream baos = new ByteArrayOutputStream();
-        InnerCNode def = new DefParser("maptypes", new StringReader(StringUtilities.implode(MaptypesConfig.CONFIG_DEF_SCHEMA, "\n"))).getTree();
-        new ConfigFileFormat(def).encode(baos, slime);
-        assertEquals(
-                "boolmap{\"foo\"} true\n" +
-                "boolmap{\"bar\"} false\n" +
-                "intmap{\"foo\"} 1234\n" +
-                "longmap{\"foo\"} 12345\n" +
-                "doublemap{\"foo\"} 3.14\n" +
-                "stringmap{\"foo\"} \"bar\"\n" +
-                "innermap{\"bar\"}.foo 1234\n" +
-                "nestedmap{\"baz\"}.inner{\"foo\"} 1234\n",
-                baos.toString());
-    }
-
-    @Test
-    public void require_that_struct_formatting_is_correct() throws IOException {
-        Slime slime = new Slime();
-        Cursor root = slime.setObject();
-        Cursor simple = root.setObject("simple");
-        simple.setString("name", "myname");
-        simple.setString("gender", "FEMALE");
-        Cursor array = simple.setArray("emails");
-        array.addString("foo@bar.com");
-        array.addString("bar@baz.net");
-
-        ByteArrayOutputStream baos = new ByteArrayOutputStream();
-        InnerCNode def = new DefParser("structtypes", new StringReader(StringUtilities.implode(StructtypesConfig.CONFIG_DEF_SCHEMA, "\n"))).getTree();
-        new ConfigFileFormat(def).encode(baos, slime);
-        assertEquals(
-                "simple.name \"myname\"\n" +
-                "simple.gender FEMALE\n" +
-                "simple.emails[0] \"foo@bar.com\"\n" +
-                "simple.emails[1] \"bar@baz.net\"\n",
-                baos.toString());
-    }
-
-    @Test
-    public void require_that_complex_struct_formatting_is_correct() throws IOException {
-        Slime slime = new Slime();
-        Cursor root = slime.setObject();
-
-        Cursor nested = root.setObject("nested");
-        Cursor nested_inner = nested.setObject("inner");
-        nested_inner.setString("name", "baz");
-        nested_inner.setString("gender", "FEMALE");
-        Cursor nested_inner_arr = nested_inner.setArray("emails");
-        nested_inner_arr.addString("foo");
-        nested_inner_arr.addString("bar");
-
-        Cursor nestedarr = root.setArray("nestedarr");
-        Cursor nestedarr1 = nestedarr.addObject();
-        Cursor inner1 = nestedarr1.setObject("inner");
-        inner1.setString("name", "foo");
-        inner1.setString("gender", "FEMALE");
-        Cursor inner1arr = inner1.setArray("emails");
-        inner1arr.addString("foo@bar");
-        inner1arr.addString("bar@foo");
-
-        Cursor complexarr = root.setArray("complexarr");
-        Cursor complexarr1 = complexarr.addObject();
-        Cursor innerarr1 = complexarr1.setArray("innerarr");
-        Cursor innerarr11 = innerarr1.addObject();
-        innerarr11.setString("name", "bar");
-        innerarr11.setString("gender", "MALE");
-
-        ByteArrayOutputStream baos = new ByteArrayOutputStream();
-        InnerCNode def = new DefParser("structtypes", new StringReader(StringUtilities.implode(StructtypesConfig.CONFIG_DEF_SCHEMA, "\n"))).getTree();
-        new ConfigFileFormat(def).encode(baos, slime);
-        assertEquals("nested.inner.name \"baz\"\n" +
-                        "nested.inner.gender FEMALE\n" +
-                        "nested.inner.emails[0] \"foo\"\n" +
-                        "nested.inner.emails[1] \"bar\"\n" +
-                        "nestedarr[0].inner.name \"foo\"\n" +
-                        "nestedarr[0].inner.gender FEMALE\n" +
-                        "nestedarr[0].inner.emails[0] \"foo@bar\"\n" +
-                        "nestedarr[0].inner.emails[1] \"bar@foo\"\n" +
-                        "complexarr[0].innerarr[0].name \"bar\"\n" +
-                        "complexarr[0].innerarr[0].gender MALE\n",
-                baos.toString());
-    }
-
-    @Test
-    public void require_that_strings_are_properly_escaped() throws IOException {
-        Slime slime = new Slime();
-        Cursor root = slime.setObject();
-        root.setString("stringval", "some\"quotes\\\"instring");
-        InnerCNode def = new DefParser("simpletypes", new StringReader(StringUtilities.implode(SimpletypesConfig.CONFIG_DEF_SCHEMA, "\n"))).getTree();
-        ByteArrayOutputStream baos = new ByteArrayOutputStream();
-        new ConfigFileFormat(def).encode(baos, slime);
-        assertEquals("stringval \"some\\\"quotes\\\\\\\"instring\"\n", baos.toString());
-    }
-
-    @Test
-    @Ignore
-    public void require_that_utf8_works() throws IOException {
-        Slime slime = new Slime();
-        Cursor root = slime.setObject();
-        final String input = "Hei \u00E6\u00F8\u00E5 \n \uBC14\uB451 \u00C6\u00D8\u00C5 hallo";
-        root.setString("stringval", input);
-        System.out.println(bytesToHexString(Utf8.toBytes(input)));
-        InnerCNode def = new DefParser("simpletypes", new StringReader(StringUtilities.implode(SimpletypesConfig.CONFIG_DEF_SCHEMA, "\n"))).getTree();
-        ByteArrayOutputStream baos = new ByteArrayOutputStream();
-        new ConfigFileFormat(def).encode(baos, slime);
-        System.out.println(bytesToHexString(baos.toByteArray()));
-        assertEquals(Utf8.toString(baos.toByteArray()), "stringval \"" + input + "\"\n");
-    }
-
-    private static String bytesToHexString(byte[] bytes){
-        StringBuilder sb = new StringBuilder();
-        for(byte b : bytes){
-            sb.append(String.format("%02x", b&0xff));
-        }
-        return sb.toString();
-    }
-}
diff --git a/container-search/src/main/java/com/yahoo/prelude/semantics/engine/RuleEvaluation.java b/container-search/src/main/java/com/yahoo/prelude/semantics/engine/RuleEvaluation.java
index 1da16b4d277..efb02034db9 100644
--- a/container-search/src/main/java/com/yahoo/prelude/semantics/engine/RuleEvaluation.java
+++ b/container-search/src/main/java/com/yahoo/prelude/semantics/engine/RuleEvaluation.java
@@ -7,7 +7,14 @@ import com.yahoo.prelude.query.TermType;
 import com.yahoo.prelude.semantics.rule.Condition;
 import com.yahoo.prelude.semantics.rule.ProductionRule;
 
-import java.util.*;
+import java.util.ArrayDeque;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.Deque;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Set;
+
 
 /**
  * A particular evaluation of a particular rule.
@@ -41,15 +48,15 @@ public class RuleEvaluation {
     private String currentContext;
 
     /** A list of referencedMatches */
-    private final List<ReferencedMatches> referencedMatchesList = new java.util.ArrayList<>();
+    private final List<ReferencedMatches> referencedMatchesList = new ArrayList<>();
 
-    private final List<Match> nonreferencedMatches = new java.util.ArrayList<>();
+    private final List<Match> nonreferencedMatches = new ArrayList<>();
 
     /** The evaluation owning this */
     private final Evaluation evaluation;
 
     /** The choice points saved in this evaluation */
-    private Stack<Choicepoint> choicepoints = null;
+    private Deque<Choicepoint> choicepoints = null;
 
     /* The last value returned by a condition evaluated in this, may be null */
     private Object value = null;
@@ -98,20 +105,18 @@ public class RuleEvaluation {
     int calculateMatchDigest(ProductionRule rule) {
         int matchDigest = rule.hashCode();
         int matchCounter = 1;
-        for (Iterator<ReferencedMatches> i = referencedMatchesList.iterator(); i.hasNext(); ) {
-            ReferencedMatches matches = i.next();
+        for (ReferencedMatches matches : referencedMatchesList) {
             int termCounter = 0;
             for (Iterator<Match> j = matches.matchIterator(); j.hasNext(); ) {
                 Match match = j.next();
-                matchDigest = 7 * matchDigest * matchCounter+
-                              71 * termCounter +
-                              match.hashCode();
+                matchDigest = 7 * matchDigest * matchCounter +
+                        71 * termCounter +
+                        match.hashCode();
                 termCounter++;
             }
             matchCounter++;
         }
-        for (Iterator<Match> i = nonreferencedMatches.iterator(); i.hasNext(); ) {
-            Match match = i.next();
+        for (Match match : nonreferencedMatches) {
             matchDigest = 7 * matchDigest * matchCounter + match.hashCode();
             matchCounter++;
         }
@@ -163,10 +168,8 @@ public class RuleEvaluation {
     public int getPosition() { return position; }
 
     /** Sets a new current label and returns the previous one */
-    public String setCurrentLabel(String currentLabel) {
-        String oldLabel = currentLabel;
+    public void setCurrentLabel(String currentLabel) {
         this.currentLabel = currentLabel;
-        return oldLabel;
     }
 
     public String getCurrentLabel() { return currentLabel; }
@@ -226,8 +229,7 @@ public class RuleEvaluation {
 
     /** Returns the referenced matches for a context name, or null if none */
     public ReferencedMatches getReferencedMatches(String name) {
-        for (Iterator<ReferencedMatches> i = referencedMatchesList.iterator(); i.hasNext(); ) {
-            ReferencedMatches matches = i.next();
+        for (ReferencedMatches matches : referencedMatchesList) {
             if (name.equals(matches.getContextName()))
                 return matches;
         }
@@ -307,7 +309,7 @@ public class RuleEvaluation {
     public Choicepoint getChoicepoint(Condition condition, boolean create) {
         if (choicepoints == null) {
             if ( ! create) return null;
-            choicepoints = new java.util.Stack<>();
+            choicepoints = new ArrayDeque<>();
         }
         Choicepoint choicepoint=lookupChoicepoint(condition);
         if (choicepoint == null) {
@@ -319,8 +321,7 @@ public class RuleEvaluation {
     }
 
     private Choicepoint lookupChoicepoint(Condition condition) {
-        for (Iterator<Choicepoint> i = choicepoints.iterator(); i.hasNext(); ) {
-            Choicepoint choicepoint = i.next();
+        for (Choicepoint choicepoint : choicepoints) {
             if (condition == choicepoint.getCondition())
                 return choicepoint;
         }
diff --git a/documentapi/src/test/java/com/yahoo/documentapi/VisitorIteratorTestCase.java b/documentapi/src/test/java/com/yahoo/documentapi/VisitorIteratorTestCase.java
index 03cd9b48de2..a50e3cd6c69 100755
--- a/documentapi/src/test/java/com/yahoo/documentapi/VisitorIteratorTestCase.java
+++ b/documentapi/src/test/java/com/yahoo/documentapi/VisitorIteratorTestCase.java
@@ -6,11 +6,12 @@ import com.yahoo.document.BucketId;
 import com.yahoo.document.BucketIdFactory;
 import org.junit.Test;
 
+import java.util.ArrayList;
 import java.util.Arrays;
+import java.util.List;
 import java.util.Map;
 import java.util.Set;
 import java.util.TreeSet;
-import java.util.Vector;
 
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
@@ -287,7 +288,7 @@ public class VisitorIteratorTestCase {
         // keeping some in the active set and some in pending
         int pendingTotal = buckets / 8;
         int activeTotal = buckets / 8;
-        Vector<VisitorIterator.BucketProgress> trackedBuckets = new Vector<VisitorIterator.BucketProgress>();
+        List<VisitorIterator.BucketProgress> trackedBuckets = new ArrayList<>();
 
         // Pre-fetch, since otherwise we'd reuse pending buckets
         for (int i = 0; i < pendingTotal + activeTotal; ++i) {
@@ -760,8 +761,8 @@ public class VisitorIteratorTestCase {
         assertTrue(bk4.compareTo(bk3) > 0);
         ProgressToken.BucketKeyWrapper bk5 = new ProgressToken.BucketKeyWrapper(0x7FFFFFFFFFFFFFFFL);
         ProgressToken.BucketKeyWrapper bk6 = new ProgressToken.BucketKeyWrapper(0x8000000000000000L);
-        assertTrue(bk5.compareTo(bk2) == 0);
-        assertTrue(bk6.compareTo(bk3) == 0);
+        assertEquals(0, bk5.compareTo(bk2));
+        assertEquals(0, bk6.compareTo(bk3));
     }
 
     private void doTestBucketKeyGeneration(int db) {
@@ -1384,16 +1385,17 @@ public class VisitorIteratorTestCase {
 
     @Test
     public void testImportProgressWithOutdatedDistribution() throws ParseException {
-        String input = "VDS bucket progress file\n" +
-                "10\n" +
-                "503\n" +
-                "500\n" +
-                "1024\n" +
-                "28000000000000be:0\n" +
-                "28000000000002be:0\n" +
-                "28000000000001be:0\n";
-
-        int db = 12;
+        String input = """
+                VDS bucket progress file
+                10
+                503
+                500
+                1024
+                28000000000000be:0
+                28000000000002be:0
+                28000000000001be:0
+                """;
+
         BucketIdFactory idFactory = new BucketIdFactory();
         ProgressToken p = new ProgressToken(input);
         assertEquals(10, p.getDistributionBitCount());
@@ -1426,14 +1428,15 @@ public class VisitorIteratorTestCase {
     public void testImportInconsistentProgressIncrease() throws ParseException {
         // Bucket progress "file" that upon time of changing from 4 to 7
         // distribution bits and writing the progress had an active bucket
-        String input = "VDS bucket progress file\n" +
-                "7\n" +
-                "32\n" +
-                "24\n" +
-                "128\n" +
-                "100000000000000c:0\n";
+        String input = """
+                VDS bucket progress file
+                7
+                32
+                24
+                128
+                100000000000000c:0
+                """;
         // Now we're at 8 distribution bits
-        int db = 8;
         BucketIdFactory idFactory = new BucketIdFactory();
         ProgressToken p = new ProgressToken(input);
         assertEquals(7, p.getDistributionBitCount());
@@ -1472,12 +1475,14 @@ public class VisitorIteratorTestCase {
     public void testImportInconsistentProgressDecrease() throws ParseException {
         // Bucket progress "file" that upon time of changing from 4 to 7
         // distribution bits and writing the progress had an active bucket
-        String input = "VDS bucket progress file\n" +
-                "7\n" +
-                "32\n" +
-                "24\n" +
-                "128\n" +
-                "100000000000000c:0\n";
+        String input = """
+                VDS bucket progress file
+                7
+                32
+                24
+                128
+                100000000000000c:0
+                """;
         BucketIdFactory idFactory = new BucketIdFactory();
         ProgressToken p = new ProgressToken(input);
 
@@ -1553,8 +1558,15 @@ public class VisitorIteratorTestCase {
         // Try to pass a known document selection to an unknown docsel iterator
         boolean caughtIt = false;
         try {
-            ProgressToken p = new ProgressToken("VDS bucket progress file\n16\n3\n1\n3\n"
-                    + "8000000000001f49:0\n8000000000001a85:0\n");
+            ProgressToken p = new ProgressToken("""
+                    VDS bucket progress file
+                    16
+                    3
+                    1
+                    3
+                    8000000000001f49:0
+                    8000000000001a85:0
+                    """);
 
             VisitorIterator.createFromDocumentSelection("id.group != \"yahoo.com\"", idFactory, 16, p);
         }
@@ -1566,14 +1578,16 @@ public class VisitorIteratorTestCase {
         // Now try it the other way around
         caughtIt = false;
         try {
-            ProgressToken p = new ProgressToken("VDS bucket progress file\n" +
-                    "10\n" +
-                    "503\n" +
-                    "500\n" +
-                    "1024\n" +
-                    "28000000000000be:0\n" +
-                    "28000000000002be:0\n" +
-                    "28000000000001be:0\n");
+            ProgressToken p = new ProgressToken("""
+                    VDS bucket progress file
+                    10
+                    503
+                    500
+                    1024
+                    28000000000000be:0
+                    28000000000002be:0
+                    28000000000001be:0
+                    """);
 
             VisitorIterator.createFromDocumentSelection("id.group=\"yahoo.com\" or id.user=555", idFactory, 16, p);
         }
@@ -1645,13 +1659,14 @@ public class VisitorIteratorTestCase {
     public void testMalformedProgressFile() {
         boolean caughtIt = false;
         try {
-            new ProgressToken("VDS bucket progress file\n" +
-                    "10\n" +
-                    "503\n" +
-                    "500\n" +
-                    "1024\n" +
-                    "28000000000000be:0\n" +
-                    "28000000000002be:");
+            new ProgressToken("""
+                    VDS bucket progress file
+                    10
+                    503
+                    500
+                    1024
+                    28000000000000be:0
+                    28000000000002be:""");
         } catch (IllegalArgumentException e) {
             caughtIt = true;
         }
@@ -1662,9 +1677,11 @@ public class VisitorIteratorTestCase {
     public void testFailOnTooFewLinesInFile() {
         boolean caughtIt = false;
         try {
-            new ProgressToken("VDS bucket progress file\n" +
-                    "10\n" +
-                    "503\n");
+            new ProgressToken("""
+                    VDS bucket progress file
+                    10
+                    503
+                    """);
         } catch (IllegalArgumentException e) {
             caughtIt = true;
         }
@@ -1675,13 +1692,14 @@ public class VisitorIteratorTestCase {
     public void testUnknownFirstHeaderLine() {
         boolean caughtIt = false;
         try {
-            new ProgressToken("Smurf Time 3000\n" +
-                    "10\n" +
-                    "503\n" +
-                    "500\n" +
-                    "1024\n" +
-                    "28000000000000be:0\n" +
-                    "28000000000002be:0");
+            new ProgressToken("""
+                    Smurf Time 3000
+                    10
+                    503
+                    500
+                    1024
+                    28000000000000be:0
+                    28000000000002be:0""");
         } catch (IllegalArgumentException e) {
             caughtIt = true;
         }
@@ -1690,14 +1708,16 @@ public class VisitorIteratorTestCase {
 
     @Test
     public void testBinaryProgressSerialization() {
-        String input = "VDS bucket progress file (48.828125% completed)\n" +
-                "10\n" +
-                "503\n" +
-                "500\n" +
-                "1024\n" +
-                "28000000000000be:0\n" +
-                "28000000000002be:0\n" +
-                "28000000000001be:0\n";
+        String input = """
+                VDS bucket progress file (48.828125% completed)
+                10
+                503
+                500
+                1024
+                28000000000000be:0
+                28000000000002be:0
+                28000000000001be:0
+                """;
         ProgressToken p = new ProgressToken(input);
         byte[] buf = p.serialize();
         ProgressToken p2 = new ProgressToken(buf);
diff --git a/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/task/util/file/FileFinder.java b/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/task/util/file/FileFinder.java
index ab702c85ffc..75da8d2c068 100644
--- a/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/task/util/file/FileFinder.java
+++ b/node-admin/src/main/java/com/yahoo/vespa/hosted/node/admin/task/util/file/FileFinder.java
@@ -14,18 +14,18 @@ import java.nio.file.SimpleFileVisitor;
 import java.nio.file.attribute.BasicFileAttributes;
 import java.time.Duration;
 import java.time.Instant;
+import java.util.ArrayDeque;
 import java.util.ArrayList;
 import java.util.Collection;
+import java.util.Deque;
 import java.util.HashSet;
 import java.util.LinkedList;
 import java.util.List;
 import java.util.Set;
-import java.util.Stack;
 import java.util.function.Consumer;
 import java.util.function.Predicate;
 import java.util.logging.Logger;
 import java.util.regex.Pattern;
-import java.util.stream.Collectors;
 import java.util.stream.Stream;
 
 /**
@@ -167,7 +167,7 @@ public class FileFinder {
             // Only need to traverse as deep as we want to match, unless we want to match everything in directories
             // already matched
             Files.walkFileTree(basePath, Set.of(), maxDepth, new SimpleFileVisitor<>() {
-                private final Stack<FileAttributes> matchingDirectoryStack = new Stack<>();
+                private final Deque<FileAttributes> matchingDirectoryStack = new ArrayDeque<>();
                 private int currentLevel = -1;
 
                 @Override
diff --git a/vdslib/src/test/java/com/yahoo/vdslib/distribution/DistributionTestCase.java b/vdslib/src/test/java/com/yahoo/vdslib/distribution/DistributionTestCase.java
index 415c4ffe8f0..f211b01415c 100644
--- a/vdslib/src/test/java/com/yahoo/vdslib/distribution/DistributionTestCase.java
+++ b/vdslib/src/test/java/com/yahoo/vdslib/distribution/DistributionTestCase.java
@@ -21,10 +21,11 @@ import java.text.ParseException;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collections;
+import java.util.Deque;
+import java.util.LinkedList;
 import java.util.List;
 import java.util.Random;
 import java.util.Set;
-import java.util.Stack;
 
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertTrue;
@@ -294,7 +295,7 @@ public class DistributionTestCase {
                 .redundancy(redundancy);
         builder.group(new StorDistributionConfig.Group.Builder()
                 .name("invalid").index("invalid").partitions(partitions));
-        Stack<Integer> nodeIndexes = new Stack<>();
+        LinkedList<Integer> nodeIndexes = new LinkedList<>();
         for (int i=0, n=getNodeCount(depth, branchCount, nodesPerLeaf); i<n; ++i) nodeIndexes.push(i);
         Collections.shuffle(nodeIndexes, new Random(123));
         addLevel(builder, "top", "", branchCount, depth, partitions, nodesPerLeaf, nodeIndexes);
@@ -302,7 +303,7 @@ public class DistributionTestCase {
     }
     private void addLevel(StorDistributionConfig.Builder builder, String namePrefix, String indexPrefix,
                           int branchCount, int depth, String partitions, int nodesPerLeaf,
-                          Stack<Integer> nodes)
+                          Deque<Integer> nodes)
     {
         for (int i=0; i<branchCount; ++i) {
             StorDistributionConfig.Group.Builder group