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/** * Copyright 2009-2019 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 * * http://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.annotation; import java.lang.annotation.Annotation; import java.lang.reflect.InvocationTargetException; import java.lang.reflect.Method; import java.lang.reflect.Modifier; import java.util.Map; import org.apache.ibatis.annotations.Lang; import org.apache.ibatis.builder.BuilderException; import org.apache.ibatis.mapping.BoundSql; import org.apache.ibatis.mapping.SqlSource; import org.apache.ibatis.reflection.ParamNameResolver; import org.apache.ibatis.scripting.LanguageDriver; import org.apache.ibatis.session.Configuration; /** * @author Clinton Begin * @author Kazuki Shimizu */ public class ProviderSqlSource implements SqlSource { private final Configuration configuration; private final Class<?> providerType; private final LanguageDriver languageDriver; private final Method mapperMethod; private final Method providerMethod; private final String[] providerMethodArgumentNames; private final Class<?>[] providerMethodParameterTypes; private final ProviderContext providerContext; private final Integer providerContextIndex; /** * @deprecated Since 3.5.3, Please use the {@link #ProviderSqlSource(Configuration, Annotation, Class, Method)} instead of this. * This constructor will remove at a future version. */ @Deprecated public ProviderSqlSource(Configuration configuration, Object provider) { this(configuration, provider, null, null); } /** * @since 3.4.5 * @deprecated Since 3.5.3, Please use the {@link #ProviderSqlSource(Configuration, Annotation, Class, Method)} instead of this. * This constructor will remove at a future version. */ @Deprecated public ProviderSqlSource(Configuration configuration, Object provider, Class<?> mapperType, Method mapperMethod) { this(configuration, (Annotation) provider, mapperType, mapperMethod); } /** * @since 3.5.3 */ public ProviderSqlSource(Configuration configuration, Annotation provider, Class<?> mapperType, Method mapperMethod) { String candidateProviderMethodName; Method candidateProviderMethod = null; try { this.configuration = configuration; this.mapperMethod = mapperMethod; Lang lang = mapperMethod == null ? null : mapperMethod.getAnnotation(Lang.class); this.languageDriver = configuration.getLanguageDriver(lang == null ? null : lang.value()); this.providerType = getProviderType(provider, mapperMethod); candidateProviderMethodName = (String) provider.annotationType().getMethod("method").invoke(provider); if (candidateProviderMethodName.length() == 0 && ProviderMethodResolver.class.isAssignableFrom(this.providerType)) { candidateProviderMethod = ((ProviderMethodResolver) this.providerType.getDeclaredConstructor() .newInstance()).resolveMethod( new ProviderContext(mapperType, mapperMethod, configuration.getDatabaseId())); } if (candidateProviderMethod == null) { candidateProviderMethodName = candidateProviderMethodName.length() == 0 ? "provideSql" : candidateProviderMethodName; for (Method m : this.providerType.getMethods()) { if (candidateProviderMethodName.equals(m.getName()) && CharSequence.class.isAssignableFrom(m.getReturnType())) { if (candidateProviderMethod != null) { throw new BuilderException("Error creating SqlSource for SqlProvider. Method '" + candidateProviderMethodName + "' is found multiple in SqlProvider '" + this.providerType.getName() + "'. Sql provider method can not overload."); } candidateProviderMethod = m; } } } } catch (BuilderException e) { throw e; } catch (Exception e) { throw new BuilderException("Error creating SqlSource for SqlProvider. Cause: " + e, e); } if (candidateProviderMethod == null) { throw new BuilderException( "Error creating SqlSource for SqlProvider. Method '" + candidateProviderMethodName + "' not found in SqlProvider '" + this.providerType.getName() + "'."); } this.providerMethod = candidateProviderMethod; this.providerMethodArgumentNames = new ParamNameResolver(configuration, this.providerMethod).getNames(); this.providerMethodParameterTypes = this.providerMethod.getParameterTypes(); ProviderContext candidateProviderContext = null; Integer candidateProviderContextIndex = null; for (int i = 0; i < this.providerMethodParameterTypes.length; i++) { Class<?> parameterType = this.providerMethodParameterTypes[i]; if (parameterType == ProviderContext.class) { if (candidateProviderContext != null) { throw new BuilderException( "Error creating SqlSource for SqlProvider. ProviderContext found multiple in SqlProvider method (" + this.providerType.getName() + "." + providerMethod.getName() + "). ProviderContext can not define multiple in SqlProvider method argument."); } candidateProviderContext = new ProviderContext(mapperType, mapperMethod, configuration.getDatabaseId()); candidateProviderContextIndex = i; } } this.providerContext = candidateProviderContext; this.providerContextIndex = candidateProviderContextIndex; } @Override public BoundSql getBoundSql(Object parameterObject) { SqlSource sqlSource = createSqlSource(parameterObject); return sqlSource.getBoundSql(parameterObject); } private SqlSource createSqlSource(Object parameterObject) { try { String sql; if (parameterObject instanceof Map) { int bindParameterCount = providerMethodParameterTypes.length - (providerContext == null ? 0 : 1); if (bindParameterCount == 1 && (providerMethodParameterTypes[Integer.valueOf(0).equals(providerContextIndex) ? 1 : 0] .isAssignableFrom(parameterObject.getClass()))) { sql = invokeProviderMethod(extractProviderMethodArguments(parameterObject)); } else { @SuppressWarnings("unchecked") Map<String, Object> params = (Map<String, Object>) parameterObject; sql = invokeProviderMethod(extractProviderMethodArguments(params, providerMethodArgumentNames)); } } else if (providerMethodParameterTypes.length == 0) { sql = invokeProviderMethod(); } else if (providerMethodParameterTypes.length == 1) { if (providerContext == null) { sql = invokeProviderMethod(parameterObject); } else { sql = invokeProviderMethod(providerContext); } } else if (providerMethodParameterTypes.length == 2) { sql = invokeProviderMethod(extractProviderMethodArguments(parameterObject)); } else { throw new BuilderException( "Cannot invoke SqlProvider method '" + providerMethod + "' with specify parameter '" + (parameterObject == null ? null : parameterObject.getClass()) + "' because SqlProvider method arguments for '" + mapperMethod + "' is an invalid combination."); } Class<?> parameterType = parameterObject == null ? Object.class : parameterObject.getClass(); return languageDriver.createSqlSource(configuration, sql, parameterType); } catch (BuilderException e) { throw e; } catch (Exception e) { throw new BuilderException("Error invoking SqlProvider method '" + providerMethod + "' with specify parameter '" + (parameterObject == null ? null : parameterObject.getClass()) + "'. Cause: " + extractRootCause(e), e); } } private Throwable extractRootCause(Exception e) { Throwable cause = e; while (cause.getCause() != null) { cause = cause.getCause(); } return cause; } private Object[] extractProviderMethodArguments(Object parameterObject) { if (providerContext != null) { Object[] args = new Object[2]; args[providerContextIndex == 0 ? 1 : 0] = parameterObject; args[providerContextIndex] = providerContext; return args; } else { return new Object[] { parameterObject }; } } private Object[] extractProviderMethodArguments(Map<String, Object> params, String[] argumentNames) { Object[] args = new Object[argumentNames.length]; for (int i = 0; i < args.length; i++) { if (providerContextIndex != null && providerContextIndex == i) { args[i] = providerContext; } else { args[i] = params.get(argumentNames[i]); } } return args; } private String invokeProviderMethod(Object... args) throws Exception { Object targetObject = null; if (!Modifier.isStatic(providerMethod.getModifiers())) { targetObject = providerType.getDeclaredConstructor().newInstance(); } CharSequence sql = (CharSequence) providerMethod.invoke(targetObject, args); return sql != null ? sql.toString() : null; } private Class<?> getProviderType(Annotation providerAnnotation, Method mapperMethod) throws NoSuchMethodException, InvocationTargetException, IllegalAccessException { Class<?> type = (Class<?>) providerAnnotation.annotationType().getMethod("type").invoke(providerAnnotation); Class<?> value = (Class<?>) providerAnnotation.annotationType().getMethod("value") .invoke(providerAnnotation); if (value == void.class && type == void.class) { throw new BuilderException("Please specify either 'value' or 'type' attribute of @" + providerAnnotation.annotationType().getSimpleName() + " at the '" + mapperMethod.toString() + "'."); } if (value != void.class && type != void.class && value != type) { throw new BuilderException("Cannot specify different class on 'value' and 'type' attribute of @" + providerAnnotation.annotationType().getSimpleName() + " at the '" + mapperMethod.toString() + "'."); } return value == void.class ? type : value; } }