Merge pull request #1284 from wuwen5/minor-code-clean

minor code clean-up.

src/main/java/org/apache/ibatis/binding/MapperProxy.java

@@ -1,5 +1,5 @@
 /**
- *    Copyright 2009-2017 the original author or authors.
+ *    Copyright 2009-2018 the original author or authors.
  *
  *    Licensed under the Apache License, Version 2.0 (the "License");
  *    you may not use this file except in compliance with the License.
@@ -60,12 +60,7 @@ public Object invoke(Object proxy, Method method, Object[] args) throws Throwabl
   }
 
   private MapperMethod cachedMapperMethod(Method method) {
-    MapperMethod mapperMethod = methodCache.get(method);
-    if (mapperMethod == null) {
-      mapperMethod = new MapperMethod(mapperInterface, method, sqlSession.getConfiguration());
-      methodCache.put(method, mapperMethod);
-    }
-    return mapperMethod;
+    return methodCache.computeIfAbsent(method, k -> new MapperMethod(mapperInterface, method, sqlSession.getConfiguration()));
   }
 
   @UsesJava7

src/main/java/org/apache/ibatis/binding/MapperProxyFactory.java

@@ -1,5 +1,5 @@
 /**
- *    Copyright 2009-2015 the original author or authors.
+ *    Copyright 2009-2018 the original author or authors.
  *
  *    Licensed under the Apache License, Version 2.0 (the "License");
  *    you may not use this file except in compliance with the License.
@@ -28,7 +28,7 @@
 public class MapperProxyFactory<T> {
 
   private final Class<T> mapperInterface;
-  private final Map<Method, MapperMethod> methodCache = new ConcurrentHashMap<Method, MapperMethod>();
+  private final Map<Method, MapperMethod> methodCache = new ConcurrentHashMap<>();
 
   public MapperProxyFactory(Class<T> mapperInterface) {
     this.mapperInterface = mapperInterface;
@@ -48,7 +48,7 @@ protected T newInstance(MapperProxy<T> mapperProxy) {
   }
 
   public T newInstance(SqlSession sqlSession) {
-    final MapperProxy<T> mapperProxy = new MapperProxy<T>(sqlSession, mapperInterface, methodCache);
+    final MapperProxy<T> mapperProxy = new MapperProxy<>(sqlSession, mapperInterface, methodCache);
     return newInstance(mapperProxy);
   }
 

src/main/java/org/apache/ibatis/binding/MapperRegistry.java

@@ -1,5 +1,5 @@
 /**
- *    Copyright 2009-2015 the original author or authors.
+ *    Copyright 2009-2018 the original author or authors.
  *
  *    Licensed under the Apache License, Version 2.0 (the "License");
  *    you may not use this file except in compliance with the License.
@@ -34,7 +34,7 @@
 public class MapperRegistry {
 
   private final Configuration config;
-  private final Map<Class<?>, MapperProxyFactory<?>> knownMappers = new HashMap<Class<?>, MapperProxyFactory<?>>();
+  private final Map<Class<?>, MapperProxyFactory<?>> knownMappers = new HashMap<>();
 
   public MapperRegistry(Configuration config) {
     this.config = config;
@@ -90,7 +90,7 @@ public Collection<Class<?>> getMappers() {
    * @since 3.2.2
    */
   public void addMappers(String packageName, Class<?> superType) {
-    ResolverUtil<Class<?>> resolverUtil = new ResolverUtil<Class<?>>();
+    ResolverUtil<Class<?>> resolverUtil = new ResolverUtil<>();
     resolverUtil.find(new ResolverUtil.IsA(superType), packageName);
     Set<Class<? extends Class<?>>> mapperSet = resolverUtil.getClasses();
     for (Class<?> mapperClass : mapperSet) {

src/main/java/org/apache/ibatis/builder/BaseBuilder.java

@@ -60,7 +60,7 @@ protected Integer integerValueOf(String value, Integer defaultValue) {
 
   protected Set<String> stringSetValueOf(String value, String defaultValue) {
     value = (value == null ? defaultValue : value);
-    return new HashSet<String>(Arrays.asList(value.split(",")));
+    return new HashSet<>(Arrays.asList(value.split(",")));
   }
 
   protected JdbcType resolveJdbcType(String alias) {

src/main/java/org/apache/ibatis/builder/MapperBuilderAssistant.java

@@ -188,7 +188,7 @@ public ResultMap addResultMap(
         throw new IncompleteElementException("Could not find a parent resultmap with id '" + extend + "'");
       }
       ResultMap resultMap = configuration.getResultMap(extend);
-      List<ResultMapping> extendedResultMappings = new ArrayList<ResultMapping>(resultMap.getResultMappings());
+      List<ResultMapping> extendedResultMappings = new ArrayList<>(resultMap.getResultMappings());
       extendedResultMappings.removeAll(resultMappings);
       // Remove parent constructor if this resultMap declares a constructor.
       boolean declaresConstructor = false;
@@ -237,7 +237,7 @@ public Discriminator buildDiscriminator(
         null,
         null,
         false);
-    Map<String, String> namespaceDiscriminatorMap = new HashMap<String, String>();
+    Map<String, String> namespaceDiscriminatorMap = new HashMap<>();
     for (Map.Entry<String, String> e : discriminatorMap.entrySet()) {
       String resultMap = e.getValue();
       resultMap = applyCurrentNamespace(resultMap, true);
@@ -320,7 +320,7 @@ private ParameterMap getStatementParameterMap(
         throw new IncompleteElementException("Could not find parameter map " + parameterMapName, e);
       }
     } else if (parameterTypeClass != null) {
-      List<ParameterMapping> parameterMappings = new ArrayList<ParameterMapping>();
+      List<ParameterMapping> parameterMappings = new ArrayList<>();
       parameterMap = new ParameterMap.Builder(
           configuration,
           statementId + "-Inline",
@@ -336,7 +336,7 @@ private List<ResultMap> getStatementResultMaps(
       String statementId) {
     resultMap = applyCurrentNamespace(resultMap, true);
 
-    List<ResultMap> resultMaps = new ArrayList<ResultMap>();
+    List<ResultMap> resultMaps = new ArrayList<>();
     if (resultMap != null) {
       String[] resultMapNames = resultMap.split(",");
       for (String resultMapName : resultMapNames) {
@@ -392,7 +392,7 @@ public ResultMapping buildResultMapping(
   }
 
   private Set<String> parseMultipleColumnNames(String columnName) {
-    Set<String> columns = new HashSet<String>();
+    Set<String> columns = new HashSet<>();
     if (columnName != null) {
       if (columnName.indexOf(',') > -1) {
         StringTokenizer parser = new StringTokenizer(columnName, "{}, ", false);
@@ -408,7 +408,7 @@ private Set<String> parseMultipleColumnNames(String columnName) {
   }
 
   private List<ResultMapping> parseCompositeColumnName(String columnName) {
-    List<ResultMapping> composites = new ArrayList<ResultMapping>();
+    List<ResultMapping> composites = new ArrayList<>();
     if (columnName != null && (columnName.indexOf('=') > -1 || columnName.indexOf(',') > -1)) {
       StringTokenizer parser = new StringTokenizer(columnName, "{}=, ", false);
       while (parser.hasMoreTokens()) {

src/main/java/org/apache/ibatis/builder/SqlSourceBuilder.java

@@ -1,5 +1,5 @@
 /**
- *    Copyright 2009-2017 the original author or authors.
+ *    Copyright 2009-2018 the original author or authors.
  *
  *    Licensed under the Apache License, Version 2.0 (the "License");
  *    you may not use this file except in compliance with the License.
@@ -48,7 +48,7 @@ public SqlSource parse(String originalSql, Class<?> parameterType, Map<String, O
 
   private static class ParameterMappingTokenHandler extends BaseBuilder implements TokenHandler {
 
-    private List<ParameterMapping> parameterMappings = new ArrayList<ParameterMapping>();
+    private List<ParameterMapping> parameterMappings = new ArrayList<>();
     private Class<?> parameterType;
     private MetaObject metaParameters;
 

src/main/java/org/apache/ibatis/builder/annotation/MapperAnnotationBuilder.java

@@ -245,7 +245,7 @@ private String generateResultMapName(Method method) {
   }
 
   private void applyResultMap(String resultMapId, Class<?> returnType, Arg[] args, Result[] results, TypeDiscriminator discriminator) {
-    List<ResultMapping> resultMappings = new ArrayList<ResultMapping>();
+    List<ResultMapping> resultMappings = new ArrayList<>();
     applyConstructorArgs(args, returnType, resultMappings);
     applyResults(results, returnType, resultMappings);
     Discriminator disc = applyDiscriminator(resultMapId, returnType, discriminator);
@@ -258,7 +258,7 @@ private void createDiscriminatorResultMaps(String resultMapId, Class<?> resultTy
     if (discriminator != null) {
       for (Case c : discriminator.cases()) {
         String caseResultMapId = resultMapId + "-" + c.value();
-        List<ResultMapping> resultMappings = new ArrayList<ResultMapping>();
+        List<ResultMapping> resultMappings = new ArrayList<>();
         // issue #136
         applyConstructorArgs(c.constructArgs(), resultType, resultMappings);
         applyResults(c.results(), resultType, resultMappings);
@@ -277,7 +277,7 @@ private Discriminator applyDiscriminator(String resultMapId, Class<?> resultType
       Class<? extends TypeHandler<?>> typeHandler = (Class<? extends TypeHandler<?>>)
               (discriminator.typeHandler() == UnknownTypeHandler.class ? null : discriminator.typeHandler());
       Case[] cases = discriminator.cases();
-      Map<String, String> discriminatorMap = new HashMap<String, String>();
+      Map<String, String> discriminatorMap = new HashMap<>();
       for (Case c : cases) {
         String value = c.value();
         String caseResultMapId = resultMapId + "-" + value;
@@ -537,7 +537,7 @@ private Class<? extends Annotation> chooseAnnotationType(Method method, Set<Clas
 
   private void applyResults(Result[] results, Class<?> resultType, List<ResultMapping> resultMappings) {
     for (Result result : results) {
-      List<ResultFlag> flags = new ArrayList<ResultFlag>();
+      List<ResultFlag> flags = new ArrayList<>();
       if (result.id()) {
         flags.add(ResultFlag.ID);
       }
@@ -593,7 +593,7 @@ private boolean hasNestedSelect(Result result) {
 
   private void applyConstructorArgs(Arg[] args, Class<?> resultType, List<ResultMapping> resultMappings) {
     for (Arg arg : args) {
-      List<ResultFlag> flags = new ArrayList<ResultFlag>();
+      List<ResultFlag> flags = new ArrayList<>();
       flags.add(ResultFlag.CONSTRUCTOR);
       if (arg.id()) {
         flags.add(ResultFlag.ID);

src/main/java/org/apache/ibatis/builder/xml/XMLIncludeTransformer.java

@@ -1,5 +1,5 @@
 /**
- *    Copyright 2009-2017 the original author or authors.
+ *    Copyright 2009-2018 the original author or authors.
  *
  *    Licensed under the Apache License, Version 2.0 (the "License");
  *    you may not use this file except in compliance with the License.
@@ -120,7 +120,7 @@ private Properties getVariablesContext(Node node, Properties inheritedVariablesC
         // Replace variables inside
         String value = PropertyParser.parse(getStringAttribute(n, "value"), inheritedVariablesContext);
         if (declaredProperties == null) {
-          declaredProperties = new HashMap<String, String>();
+          declaredProperties = new HashMap<>();
         }
         if (declaredProperties.put(name, value) != null) {
           throw new BuilderException("Variable " + name + " defined twice in the same include definition");

src/main/java/org/apache/ibatis/builder/xml/XMLMapperBuilder.java

@@ -217,7 +217,7 @@ private void parameterMapElement(List<XNode> list) throws Exception {
       String type = parameterMapNode.getStringAttribute("type");
       Class<?> parameterClass = resolveClass(type);
       List<XNode> parameterNodes = parameterMapNode.evalNodes("parameter");
-      List<ParameterMapping> parameterMappings = new ArrayList<ParameterMapping>();
+      List<ParameterMapping> parameterMappings = new ArrayList<>();
       for (XNode parameterNode : parameterNodes) {
         String property = parameterNode.getStringAttribute("property");
         String javaType = parameterNode.getStringAttribute("javaType");
@@ -264,7 +264,7 @@ private ResultMap resultMapElement(XNode resultMapNode, List<ResultMapping> addi
     Boolean autoMapping = resultMapNode.getBooleanAttribute("autoMapping");
     Class<?> typeClass = resolveClass(type);
     Discriminator discriminator = null;
-    List<ResultMapping> resultMappings = new ArrayList<ResultMapping>();
+    List<ResultMapping> resultMappings = new ArrayList<>();
     resultMappings.addAll(additionalResultMappings);
     List<XNode> resultChildren = resultMapNode.getChildren();
     for (XNode resultChild : resultChildren) {
@@ -273,7 +273,7 @@ private ResultMap resultMapElement(XNode resultMapNode, List<ResultMapping> addi
       } else if ("discriminator".equals(resultChild.getName())) {
         discriminator = processDiscriminatorElement(resultChild, typeClass, resultMappings);
       } else {
-        List<ResultFlag> flags = new ArrayList<ResultFlag>();
+        List<ResultFlag> flags = new ArrayList<>();
         if ("id".equals(resultChild.getName())) {
           flags.add(ResultFlag.ID);
         }
@@ -292,7 +292,7 @@ private ResultMap resultMapElement(XNode resultMapNode, List<ResultMapping> addi
   private void processConstructorElement(XNode resultChild, Class<?> resultType, List<ResultMapping> resultMappings) throws Exception {
     List<XNode> argChildren = resultChild.getChildren();
     for (XNode argChild : argChildren) {
-      List<ResultFlag> flags = new ArrayList<ResultFlag>();
+      List<ResultFlag> flags = new ArrayList<>();
       flags.add(ResultFlag.CONSTRUCTOR);
       if ("idArg".equals(argChild.getName())) {
         flags.add(ResultFlag.ID);
@@ -310,7 +310,7 @@ private Discriminator processDiscriminatorElement(XNode context, Class<?> result
     @SuppressWarnings("unchecked")
     Class<? extends TypeHandler<?>> typeHandlerClass = (Class<? extends TypeHandler<?>>) resolveClass(typeHandler);
     JdbcType jdbcTypeEnum = resolveJdbcType(jdbcType);
-    Map<String, String> discriminatorMap = new HashMap<String, String>();
+    Map<String, String> discriminatorMap = new HashMap<>();
     for (XNode caseChild : context.getChildren()) {
       String value = caseChild.getStringAttribute("value");
       String resultMap = caseChild.getStringAttribute("resultMap", processNestedResultMappings(caseChild, resultMappings));

src/main/java/org/apache/ibatis/cache/CacheKey.java

@@ -1,5 +1,5 @@
 /**
- *    Copyright 2009-2017 the original author or authors.
+ *    Copyright 2009-2018 the original author or authors.
  *
  *    Licensed under the Apache License, Version 2.0 (the "License");
  *    you may not use this file except in compliance with the License.
@@ -44,7 +44,7 @@ public CacheKey() {
     this.hashcode = DEFAULT_HASHCODE;
     this.multiplier = DEFAULT_MULTIPLYER;
     this.count = 0;
-    this.updateList = new ArrayList<Object>();
+    this.updateList = new ArrayList<>();
   }
 
   public CacheKey(Object[] objects) {
@@ -122,7 +122,7 @@ public String toString() {
   @Override
   public CacheKey clone() throws CloneNotSupportedException {
     CacheKey clonedCacheKey = (CacheKey) super.clone();
-    clonedCacheKey.updateList = new ArrayList<Object>(updateList);
+    clonedCacheKey.updateList = new ArrayList<>(updateList);
     return clonedCacheKey;
   }
 

src/main/java/org/apache/ibatis/cache/TransactionalCacheManager.java

@@ -1,5 +1,5 @@
 /**
- *    Copyright 2009-2017 the original author or authors.
+ *    Copyright 2009-2018 the original author or authors.
  *
  *    Licensed under the Apache License, Version 2.0 (the "License");
  *    you may not use this file except in compliance with the License.
@@ -25,7 +25,7 @@
  */
 public class TransactionalCacheManager {
 
-  private final Map<Cache, TransactionalCache> transactionalCaches = new HashMap<Cache, TransactionalCache>();
+  private final Map<Cache, TransactionalCache> transactionalCaches = new HashMap<>();
 
   public void clear(Cache cache) {
     getTransactionalCache(cache).clear();
@@ -52,12 +52,7 @@ public void rollback() {
   }
 
   private TransactionalCache getTransactionalCache(Cache cache) {
-    TransactionalCache txCache = transactionalCaches.get(cache);
-    if (txCache == null) {
-      txCache = new TransactionalCache(cache);
-      transactionalCaches.put(cache, txCache);
-    }
-    return txCache;
+    return transactionalCaches.computeIfAbsent(cache, TransactionalCache::new);
   }
 
 }

src/main/java/org/apache/ibatis/cache/decorators/BlockingCache.java

@@ -1,5 +1,5 @@
 /**
- *    Copyright 2009-2015 the original author or authors.
+ *    Copyright 2009-2018 the original author or authors.
  *
  *    Licensed under the Apache License, Version 2.0 (the "License");
  *    you may not use this file except in compliance with the License.
@@ -42,7 +42,7 @@ public class BlockingCache implements Cache {
 
   public BlockingCache(Cache delegate) {
     this.delegate = delegate;
-    this.locks = new ConcurrentHashMap<Object, ReentrantLock>();
+    this.locks = new ConcurrentHashMap<>();
   }
 
   @Override

src/main/java/org/apache/ibatis/cache/decorators/FifoCache.java

@@ -1,5 +1,5 @@
 /**
- *    Copyright 2009-2017 the original author or authors.
+ *    Copyright 2009-2018 the original author or authors.
  *
  *    Licensed under the Apache License, Version 2.0 (the "License");
  *    you may not use this file except in compliance with the License.
@@ -34,7 +34,7 @@ public class FifoCache implements Cache {
 
   public FifoCache(Cache delegate) {
     this.delegate = delegate;
-    this.keyList = new LinkedList<Object>();
+    this.keyList = new LinkedList<>();
     this.size = 1024;
   }
 

src/main/java/org/apache/ibatis/cache/decorators/SoftCache.java

@@ -1,5 +1,5 @@
 /**
- *    Copyright 2009-2015 the original author or authors.
+ *    Copyright 2009-2018 the original author or authors.
  *
  *    Licensed under the Apache License, Version 2.0 (the "License");
  *    you may not use this file except in compliance with the License.
@@ -38,8 +38,8 @@ public class SoftCache implements Cache {
   public SoftCache(Cache delegate) {
     this.delegate = delegate;
     this.numberOfHardLinks = 256;
-    this.hardLinksToAvoidGarbageCollection = new LinkedList<Object>();
-    this.queueOfGarbageCollectedEntries = new ReferenceQueue<Object>();
+    this.hardLinksToAvoidGarbageCollection = new LinkedList<>();
+    this.queueOfGarbageCollectedEntries = new ReferenceQueue<>();
   }
 
   @Override

src/main/java/org/apache/ibatis/cache/decorators/TransactionalCache.java

@@ -1,5 +1,5 @@
 /**
- *    Copyright 2009-2017 the original author or authors.
+ *    Copyright 2009-2018 the original author or authors.
  *
  *    Licensed under the Apache License, Version 2.0 (the "License");
  *    you may not use this file except in compliance with the License.
@@ -48,8 +48,8 @@ public class TransactionalCache implements Cache {
   public TransactionalCache(Cache delegate) {
     this.delegate = delegate;
     this.clearOnCommit = false;
-    this.entriesToAddOnCommit = new HashMap<Object, Object>();
-    this.entriesMissedInCache = new HashSet<Object>();
+    this.entriesToAddOnCommit = new HashMap<>();
+    this.entriesMissedInCache = new HashSet<>();
   }
 
   @Override

src/main/java/org/apache/ibatis/cache/decorators/WeakCache.java

@@ -1,5 +1,5 @@
 /**
- *    Copyright 2009-2015 the original author or authors.
+ *    Copyright 2009-2018 the original author or authors.
  *
  *    Licensed under the Apache License, Version 2.0 (the "License");
  *    you may not use this file except in compliance with the License.
@@ -38,8 +38,8 @@ public class WeakCache implements Cache {
   public WeakCache(Cache delegate) {
     this.delegate = delegate;
     this.numberOfHardLinks = 256;
-    this.hardLinksToAvoidGarbageCollection = new LinkedList<Object>();
-    this.queueOfGarbageCollectedEntries = new ReferenceQueue<Object>();
+    this.hardLinksToAvoidGarbageCollection = new LinkedList<>();
+    this.queueOfGarbageCollectedEntries = new ReferenceQueue<>();
   }
 
   @Override