Java tutorial
/** * Licensed to the Apache Software Foundation (ASF) under one * or more contributor license agreements. See the NOTICE file * distributed with this work for additional information * regarding copyright ownership. The ASF licenses this file * to you 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 com.gst.infrastructure.codes.domain; import java.util.LinkedHashMap; import java.util.Map; import java.util.Set; import javax.persistence.CascadeType; import javax.persistence.Column; import javax.persistence.Entity; import javax.persistence.FetchType; import javax.persistence.OneToMany; import javax.persistence.Table; import javax.persistence.UniqueConstraint; import org.apache.commons.lang.StringUtils; import com.gst.infrastructure.codes.exception.SystemDefinedCodeCannotBeChangedException; import com.gst.infrastructure.core.api.JsonCommand; import com.gst.infrastructure.core.domain.AbstractPersistableCustom; @Entity @Table(name = "m_code", uniqueConstraints = { @UniqueConstraint(columnNames = { "code_name" }, name = "code_name") }) public class Code extends AbstractPersistableCustom<Long> { @Column(name = "code_name", length = 100) private String name; @Column(name = "is_system_defined") private boolean systemDefined; @OneToMany(fetch = FetchType.EAGER, cascade = CascadeType.ALL, mappedBy = "code", orphanRemoval = true) private Set<CodeValue> values; public static Code fromJson(final JsonCommand command) { final String name = command.stringValueOfParameterNamed("name"); return new Code(name); } public static Code createNew(final String name) { return new Code(name); } protected Code() { this.systemDefined = false; } private Code(final String name) { this.name = name; this.systemDefined = false; } public String name() { return this.name; } public boolean isSystemDefined() { return this.systemDefined; } public Map<String, Object> update(final JsonCommand command) { if (this.systemDefined) { throw new SystemDefinedCodeCannotBeChangedException(); } final Map<String, Object> actualChanges = new LinkedHashMap<>(1); final String firstnameParamName = "name"; if (command.isChangeInStringParameterNamed(firstnameParamName, this.name)) { final String newValue = command.stringValueOfParameterNamed(firstnameParamName); actualChanges.put(firstnameParamName, newValue); this.name = StringUtils.defaultIfEmpty(newValue, null); } return actualChanges; } public boolean remove(final CodeValue codeValueToDelete) { return this.values.remove(codeValueToDelete); } }