Java tutorial
package com.thinkbiganalytics.util; /*- * #%L * thinkbig-nifi-core-processors * %% * Copyright (C) 2017 ThinkBig Analytics * %% * 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. * #L% */ import com.thinkbiganalytics.hive.util.HiveUtils; import org.apache.commons.lang3.StringUtils; import org.apache.commons.lang3.Validate; import java.util.ArrayList; import java.util.Arrays; import java.util.List; /** */ public class PartitionKey implements Cloneable { private String alias; private String key; private String type; private String formula; public PartitionKey(String key, String type, String formula) { Validate.notEmpty(key); Validate.notEmpty(type); Validate.notEmpty(formula); this.key = key.trim().toLowerCase(); this.type = type.trim().toLowerCase(); this.formula = formula.trim().toLowerCase(); } public static PartitionKey createFromString(String value) { if (StringUtils.isEmpty(value)) { return null; } String[] values = value.split("\\|"); if (values.length != 3) { throw new RuntimeException("Expecting format field|type|formula got " + value); } return new PartitionKey(values[0], values[1], values[2]); } public static PartitionKey[] partitionKeysForTableAlias(PartitionKey[] keys, String alias) { List<PartitionKey> partitionKeys = new ArrayList<>(); Arrays.stream(keys).forEach(key -> { try { PartitionKey clonedKey = (PartitionKey) key.clone(); clonedKey.setAlias(alias); partitionKeys.add(clonedKey); } catch (CloneNotSupportedException e) { e.printStackTrace(); } }); return partitionKeys.toArray(new PartitionKey[0]); } public String getKey() { return key; } public String getKeyForSql() { return HiveUtils.quoteIdentifier(key); } public String getKeyWithAlias() { return toAliasSQL() + getKeyForSql(); } public String getFormula() { return formula.indexOf('(') > -1 ? formula : HiveUtils.quoteIdentifier(key); } public String getFormulaWithAlias() { surroundFormulaColumnWithTick(); if (alias != null) { int idx = formula.indexOf("("); if (idx > -1) { StringBuffer sb = new StringBuffer(formula); sb.insert(idx + 1, alias + "."); return sb.toString(); } return getKeyWithAlias(); } return getFormula(); } /** * if column in formula has a space, surround it with a tick mark */ private void surroundFormulaColumnWithTick() { int idx = formula.indexOf("("); String column = StringUtils.substringBetween(formula, "(", ")"); if (StringUtils.isNotBlank(column) && column.charAt(0) != '`') { column = HiveUtils.quoteIdentifier(column); StringBuffer sb = new StringBuffer(); sb.append(StringUtils.substringBefore(formula, "(")).append("(").append(column).append(")"); formula = sb.toString(); } } /** * Generates the where statement against the source table using the provided value */ public String toSourceSQLWhere(String value) { if ("string".equalsIgnoreCase(type)) { return formula + "='" + value + "'"; } else { return formula + "=" + value; } } /** * Generates the where statement against the target table using the provided value */ public String toTargetSQLWhere(String value) { return toPartitionNameValue(value); } private String toAliasSQL() { return (alias != null ? alias + "." : ""); } /** * Generates the partition specification portion using the value */ public String toPartitionNameValue(String value) { if ("string".equalsIgnoreCase(type)) { return toAliasSQL() + getKeyForSql() + "='" + value + "'"; } else { return toAliasSQL() + getKeyForSql() + "=" + value; } } public String getAlias() { return alias; } private void setAlias(String alias) { this.alias = alias; } }