org.apache.ibatis.builder.xml.XMLMapperBuilder Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of mybatis Show documentation
The MyBatis SQL mapper framework makes it easier to use a relational database with object-oriented applications. MyBatis couples objects with stored procedures or SQL statements using a XML descriptor or annotations. Simplicity is the biggest advantage of the MyBatis data mapper over object relational mapping tools.
There is a newer version: 3.5.16
Show newest version
/*
 *    Copyright 2009-2023 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.
 *    You may obtain a copy of the License at
 *
 *       https://www.apache.org/licenses/LICENSE-2.0
 *
 *    Unless required by applicable law or agreed to in writing, software
 *    distributed under the License is distributed on an "AS IS" BASIS,
 *    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *    See the License for the specific language governing permissions and
 *    limitations under the License.
 */
package org.apache.ibatis.builder.xml;

import java.io.InputStream;
import java.io.Reader;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Properties;

import org.apache.ibatis.builder.BaseBuilder;
import org.apache.ibatis.builder.BuilderException;
import org.apache.ibatis.builder.CacheRefResolver;
import org.apache.ibatis.builder.IncompleteElementException;
import org.apache.ibatis.builder.MapperBuilderAssistant;
import org.apache.ibatis.builder.ResultMapResolver;
import org.apache.ibatis.cache.Cache;
import org.apache.ibatis.executor.ErrorContext;
import org.apache.ibatis.io.Resources;
import org.apache.ibatis.mapping.Discriminator;
import org.apache.ibatis.mapping.ParameterMapping;
import org.apache.ibatis.mapping.ParameterMode;
import org.apache.ibatis.mapping.ResultFlag;
import org.apache.ibatis.mapping.ResultMap;
import org.apache.ibatis.mapping.ResultMapping;
import org.apache.ibatis.parsing.XNode;
import org.apache.ibatis.parsing.XPathParser;
import org.apache.ibatis.reflection.MetaClass;
import org.apache.ibatis.session.Configuration;
import org.apache.ibatis.type.JdbcType;
import org.apache.ibatis.type.TypeHandler;

/**
 * @author Clinton Begin
 * @author Kazuki Shimizu
 */
public class XMLMapperBuilder extends BaseBuilder {

  private final XPathParser parser;
  private final MapperBuilderAssistant builderAssistant;
  private final Map sqlFragments;
  private final String resource;

  @Deprecated
  public XMLMapperBuilder(Reader reader, Configuration configuration, String resource, Map sqlFragments,
      String namespace) {
    this(reader, configuration, resource, sqlFragments);
    this.builderAssistant.setCurrentNamespace(namespace);
  }

  @Deprecated
  public XMLMapperBuilder(Reader reader, Configuration configuration, String resource,
      Map sqlFragments) {
    this(new XPathParser(reader, true, configuration.getVariables(), new XMLMapperEntityResolver()), configuration,
        resource, sqlFragments);
  }

  public XMLMapperBuilder(InputStream inputStream, Configuration configuration, String resource,
      Map sqlFragments, String namespace) {
    this(inputStream, configuration, resource, sqlFragments);
    this.builderAssistant.setCurrentNamespace(namespace);
  }

  public XMLMapperBuilder(InputStream inputStream, Configuration configuration, String resource,
      Map sqlFragments) {
    this(new XPathParser(inputStream, true, configuration.getVariables(), new XMLMapperEntityResolver()), configuration,
        resource, sqlFragments);
  }

  private XMLMapperBuilder(XPathParser parser, Configuration configuration, String resource,
      Map sqlFragments) {
    super(configuration);
    this.builderAssistant = new MapperBuilderAssistant(configuration, resource);
    this.parser = parser;
    this.sqlFragments = sqlFragments;
    this.resource = resource;
  }

  public void parse() {
    if (!configuration.isResourceLoaded(resource)) {
      configurationElement(parser.evalNode("/mapper"));
      configuration.addLoadedResource(resource);
      bindMapperForNamespace();
    }

    parsePendingResultMaps();
    parsePendingCacheRefs();
    parsePendingStatements();
  }

  public XNode getSqlFragment(String refid) {
    return sqlFragments.get(refid);
  }

  private void configurationElement(XNode context) {
    try {
      String namespace = context.getStringAttribute("namespace");
      if (namespace == null || namespace.isEmpty()) {
        throw new BuilderException("Mapper's namespace cannot be empty");
      }
      builderAssistant.setCurrentNamespace(namespace);
      cacheRefElement(context.evalNode("cache-ref"));
      cacheElement(context.evalNode("cache"));
      parameterMapElement(context.evalNodes("/mapper/parameterMap"));
      resultMapElements(context.evalNodes("/mapper/resultMap"));
      sqlElement(context.evalNodes("/mapper/sql"));
      buildStatementFromContext(context.evalNodes("select|insert|update|delete"));
    } catch (Exception e) {
      throw new BuilderException("Error parsing Mapper XML. The XML location is '" + resource + "'. Cause: " + e, e);
    }
  }

  private void buildStatementFromContext(List list) {
    if (configuration.getDatabaseId() != null) {
      buildStatementFromContext(list, configuration.getDatabaseId());
    }
    buildStatementFromContext(list, null);
  }

  private void buildStatementFromContext(List list, String requiredDatabaseId) {
    for (XNode context : list) {
      final XMLStatementBuilder statementParser = new XMLStatementBuilder(configuration, builderAssistant, context,
          requiredDatabaseId);
      try {
        statementParser.parseStatementNode();
      } catch (IncompleteElementException e) {
        configuration.addIncompleteStatement(statementParser);
      }
    }
  }

  private void parsePendingResultMaps() {
    Collection incompleteResultMaps = configuration.getIncompleteResultMaps();
    synchronized (incompleteResultMaps) {
      Iterator iter = incompleteResultMaps.iterator();
      while (iter.hasNext()) {
        try {
          iter.next().resolve();
          iter.remove();
        } catch (IncompleteElementException e) {
          // ResultMap is still missing a resource...
        }
      }
    }
  }

  private void parsePendingCacheRefs() {
    Collection incompleteCacheRefs = configuration.getIncompleteCacheRefs();
    synchronized (incompleteCacheRefs) {
      Iterator iter = incompleteCacheRefs.iterator();
      while (iter.hasNext()) {
        try {
          iter.next().resolveCacheRef();
          iter.remove();
        } catch (IncompleteElementException e) {
          // Cache ref is still missing a resource...
        }
      }
    }
  }

  private void parsePendingStatements() {
    Collection incompleteStatements = configuration.getIncompleteStatements();
    synchronized (incompleteStatements) {
      Iterator iter = incompleteStatements.iterator();
      while (iter.hasNext()) {
        try {
          iter.next().parseStatementNode();
          iter.remove();
        } catch (IncompleteElementException e) {
          // Statement is still missing a resource...
        }
      }
    }
  }

  private void cacheRefElement(XNode context) {
    if (context != null) {
      configuration.addCacheRef(builderAssistant.getCurrentNamespace(), context.getStringAttribute("namespace"));
      CacheRefResolver cacheRefResolver = new CacheRefResolver(builderAssistant,
          context.getStringAttribute("namespace"));
      try {
        cacheRefResolver.resolveCacheRef();
      } catch (IncompleteElementException e) {
        configuration.addIncompleteCacheRef(cacheRefResolver);
      }
    }
  }

  private void cacheElement(XNode context) {
    if (context != null) {
      String type = context.getStringAttribute("type", "PERPETUAL");
      Class typeClass = typeAliasRegistry.resolveAlias(type);
      String eviction = context.getStringAttribute("eviction", "LRU");
      Class evictionClass = typeAliasRegistry.resolveAlias(eviction);
      Long flushInterval = context.getLongAttribute("flushInterval");
      Integer size = context.getIntAttribute("size");
      boolean readWrite = !context.getBooleanAttribute("readOnly", false);
      boolean blocking = context.getBooleanAttribute("blocking", false);
      Properties props = context.getChildrenAsProperties();
      builderAssistant.useNewCache(typeClass, evictionClass, flushInterval, size, readWrite, blocking, props);
    }
  }

  private void parameterMapElement(List list) {
    for (XNode parameterMapNode : list) {
      String id = parameterMapNode.getStringAttribute("id");
      String type = parameterMapNode.getStringAttribute("type");
      Class parameterClass = resolveClass(type);
      List parameterNodes = parameterMapNode.evalNodes("parameter");
      List parameterMappings = new ArrayList<>();
      for (XNode parameterNode : parameterNodes) {
        String property = parameterNode.getStringAttribute("property");
        String javaType = parameterNode.getStringAttribute("javaType");
        String jdbcType = parameterNode.getStringAttribute("jdbcType");
        String resultMap = parameterNode.getStringAttribute("resultMap");
        String mode = parameterNode.getStringAttribute("mode");
        String typeHandler = parameterNode.getStringAttribute("typeHandler");
        Integer numericScale = parameterNode.getIntAttribute("numericScale");
        ParameterMode modeEnum = resolveParameterMode(mode);
        Class javaTypeClass = resolveClass(javaType);
        JdbcType jdbcTypeEnum = resolveJdbcType(jdbcType);
        Class> typeHandlerClass = resolveClass(typeHandler);
        ParameterMapping parameterMapping = builderAssistant.buildParameterMapping(parameterClass, property,
            javaTypeClass, jdbcTypeEnum, resultMap, modeEnum, typeHandlerClass, numericScale);
        parameterMappings.add(parameterMapping);
      }
      builderAssistant.addParameterMap(id, parameterClass, parameterMappings);
    }
  }

  private void resultMapElements(List list) {
    for (XNode resultMapNode : list) {
      try {
        resultMapElement(resultMapNode);
      } catch (IncompleteElementException e) {
        // ignore, it will be retried
      }
    }
  }

  private ResultMap resultMapElement(XNode resultMapNode) {
    return resultMapElement(resultMapNode, Collections.emptyList(), null);
  }

  private ResultMap resultMapElement(XNode resultMapNode, List additionalResultMappings,
      Class enclosingType) {
    ErrorContext.instance().activity("processing " + resultMapNode.getValueBasedIdentifier());
    String type = resultMapNode.getStringAttribute("type", resultMapNode.getStringAttribute("ofType",
        resultMapNode.getStringAttribute("resultType", resultMapNode.getStringAttribute("javaType"))));
    Class typeClass = resolveClass(type);
    if (typeClass == null) {
      typeClass = inheritEnclosingType(resultMapNode, enclosingType);
    }
    Discriminator discriminator = null;
    List resultMappings = new ArrayList<>(additionalResultMappings);
    List resultChildren = resultMapNode.getChildren();
    for (XNode resultChild : resultChildren) {
      if ("constructor".equals(resultChild.getName())) {
        processConstructorElement(resultChild, typeClass, resultMappings);
      } else if ("discriminator".equals(resultChild.getName())) {
        discriminator = processDiscriminatorElement(resultChild, typeClass, resultMappings);
      } else {
        List flags = new ArrayList<>();
        if ("id".equals(resultChild.getName())) {
          flags.add(ResultFlag.ID);
        }
        resultMappings.add(buildResultMappingFromContext(resultChild, typeClass, flags));
      }
    }
    String id = resultMapNode.getStringAttribute("id", resultMapNode.getValueBasedIdentifier());
    String extend = resultMapNode.getStringAttribute("extends");
    Boolean autoMapping = resultMapNode.getBooleanAttribute("autoMapping");
    ResultMapResolver resultMapResolver = new ResultMapResolver(builderAssistant, id, typeClass, extend, discriminator,
        resultMappings, autoMapping);
    try {
      return resultMapResolver.resolve();
    } catch (IncompleteElementException e) {
      configuration.addIncompleteResultMap(resultMapResolver);
      throw e;
    }
  }

  protected Class inheritEnclosingType(XNode resultMapNode, Class enclosingType) {
    if ("association".equals(resultMapNode.getName()) && resultMapNode.getStringAttribute("resultMap") == null) {
      String property = resultMapNode.getStringAttribute("property");
      if (property != null && enclosingType != null) {
        MetaClass metaResultType = MetaClass.forClass(enclosingType, configuration.getReflectorFactory());
        return metaResultType.getSetterType(property);
      }
    } else if ("case".equals(resultMapNode.getName()) && resultMapNode.getStringAttribute("resultMap") == null) {
      return enclosingType;
    }
    return null;
  }

  private void processConstructorElement(XNode resultChild, Class resultType, List resultMappings) {
    List argChildren = resultChild.getChildren();
    for (XNode argChild : argChildren) {
      List flags = new ArrayList<>();
      flags.add(ResultFlag.CONSTRUCTOR);
      if ("idArg".equals(argChild.getName())) {
        flags.add(ResultFlag.ID);
      }
      resultMappings.add(buildResultMappingFromContext(argChild, resultType, flags));
    }
  }

  private Discriminator processDiscriminatorElement(XNode context, Class resultType,
      List resultMappings) {
    String column = context.getStringAttribute("column");
    String javaType = context.getStringAttribute("javaType");
    String jdbcType = context.getStringAttribute("jdbcType");
    String typeHandler = context.getStringAttribute("typeHandler");
    Class javaTypeClass = resolveClass(javaType);
    Class> typeHandlerClass = resolveClass(typeHandler);
    JdbcType jdbcTypeEnum = resolveJdbcType(jdbcType);
    Map discriminatorMap = new HashMap<>();
    for (XNode caseChild : context.getChildren()) {
      String value = caseChild.getStringAttribute("value");
      String resultMap = caseChild.getStringAttribute("resultMap",
          processNestedResultMappings(caseChild, resultMappings, resultType));
      discriminatorMap.put(value, resultMap);
    }
    return builderAssistant.buildDiscriminator(resultType, column, javaTypeClass, jdbcTypeEnum, typeHandlerClass,
        discriminatorMap);
  }

  private void sqlElement(List list) {
    if (configuration.getDatabaseId() != null) {
      sqlElement(list, configuration.getDatabaseId());
    }
    sqlElement(list, null);
  }

  private void sqlElement(List list, String requiredDatabaseId) {
    for (XNode context : list) {
      String databaseId = context.getStringAttribute("databaseId");
      String id = context.getStringAttribute("id");
      id = builderAssistant.applyCurrentNamespace(id, false);
      if (databaseIdMatchesCurrent(id, databaseId, requiredDatabaseId)) {
        sqlFragments.put(id, context);
      }
    }
  }

  private boolean databaseIdMatchesCurrent(String id, String databaseId, String requiredDatabaseId) {
    if (requiredDatabaseId != null) {
      return requiredDatabaseId.equals(databaseId);
    }
    if (databaseId != null) {
      return false;
    }
    if (!this.sqlFragments.containsKey(id)) {
      return true;
    }
    // skip this fragment if there is a previous one with a not null databaseId
    XNode context = this.sqlFragments.get(id);
    return context.getStringAttribute("databaseId") == null;
  }

  private ResultMapping buildResultMappingFromContext(XNode context, Class resultType, List flags) {
    String property;
    if (flags.contains(ResultFlag.CONSTRUCTOR)) {
      property = context.getStringAttribute("name");
    } else {
      property = context.getStringAttribute("property");
    }
    String column = context.getStringAttribute("column");
    String javaType = context.getStringAttribute("javaType");
    String jdbcType = context.getStringAttribute("jdbcType");
    String nestedSelect = context.getStringAttribute("select");
    String nestedResultMap = context.getStringAttribute("resultMap",
        () -> processNestedResultMappings(context, Collections.emptyList(), resultType));
    String notNullColumn = context.getStringAttribute("notNullColumn");
    String columnPrefix = context.getStringAttribute("columnPrefix");
    String typeHandler = context.getStringAttribute("typeHandler");
    String resultSet = context.getStringAttribute("resultSet");
    String foreignColumn = context.getStringAttribute("foreignColumn");
    boolean lazy = "lazy"
        .equals(context.getStringAttribute("fetchType", configuration.isLazyLoadingEnabled() ? "lazy" : "eager"));
    Class javaTypeClass = resolveClass(javaType);
    Class> typeHandlerClass = resolveClass(typeHandler);
    JdbcType jdbcTypeEnum = resolveJdbcType(jdbcType);
    return builderAssistant.buildResultMapping(resultType, property, column, javaTypeClass, jdbcTypeEnum, nestedSelect,
        nestedResultMap, notNullColumn, columnPrefix, typeHandlerClass, flags, resultSet, foreignColumn, lazy);
  }

  private String processNestedResultMappings(XNode context, List resultMappings,
      Class enclosingType) {
    if (Arrays.asList("association", "collection", "case").contains(context.getName())
        && context.getStringAttribute("select") == null) {
      validateCollection(context, enclosingType);
      ResultMap resultMap = resultMapElement(context, resultMappings, enclosingType);
      return resultMap.getId();
    }
    return null;
  }

  protected void validateCollection(XNode context, Class enclosingType) {
    if ("collection".equals(context.getName()) && context.getStringAttribute("resultMap") == null
        && context.getStringAttribute("javaType") == null) {
      MetaClass metaResultType = MetaClass.forClass(enclosingType, configuration.getReflectorFactory());
      String property = context.getStringAttribute("property");
      if (!metaResultType.hasSetter(property)) {
        throw new BuilderException(
            "Ambiguous collection type for property '" + property + "'. You must specify 'javaType' or 'resultMap'.");
      }
    }
  }

  private void bindMapperForNamespace() {
    String namespace = builderAssistant.getCurrentNamespace();
    if (namespace != null) {
      Class boundType = null;
      try {
        boundType = Resources.classForName(namespace);
      } catch (ClassNotFoundException e) {
        // ignore, bound type is not required
      }
      if (boundType != null && !configuration.hasMapper(boundType)) {
        // Spring may not know the real resource name so we set a flag
        // to prevent loading again this resource from the mapper interface
        // look at MapperAnnotationBuilder#loadXmlResource
        configuration.addLoadedResource("namespace:" + namespace);
        configuration.addMapper(boundType);
      }
    }
  }

}