Remove un-used code for jump-to-item queries

spring-batch-infrastructure/src/main/java/org/springframework/batch/item/database/AbstractPagingItemReader.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2006-2019 the original author or authors.
+ * Copyright 2006-2022 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.
@@ -156,14 +156,10 @@ protected void jumpToItem(int itemIndex) throws Exception {
 			current = itemIndex % pageSize;
 		}
 
-		doJumpToPage(itemIndex);
-
 		if (logger.isDebugEnabled()) {
 			logger.debug("Jumping to page " + getPage() + " and index " + current);
 		}
 
 	}
 
-	abstract protected void doJumpToPage(int itemIndex);
-
 }

spring-batch-infrastructure/src/main/java/org/springframework/batch/item/database/HibernatePagingItemReader.java

@@ -157,10 +157,6 @@ protected void doReadPage() {
 
 	}
 
-	@Override
-	protected void doJumpToPage(int itemIndex) {
-	}
-
 	@Override
 	protected void doClose() throws Exception {
 		helper.close();

spring-batch-infrastructure/src/main/java/org/springframework/batch/item/database/JdbcPagingItemReader.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2006-2021 the original author or authors.
+ * Copyright 2006-2022 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.
@@ -254,33 +254,6 @@ public void open(ExecutionContext executionContext) {
 		super.open(executionContext);
 	}
 
-	@Override
-	protected void doJumpToPage(int itemIndex) {
-		/*
-		 * Normally this would be false (the startAfterValue is enough information to
-		 * restart from.
-		 */
-		// TODO: this is dead code, startAfterValues is never null - see
-		// #open(ExecutionContext)
-		if (startAfterValues == null && getPage() > 0) {
-
-			String jumpToItemSql = queryProvider.generateJumpToItemQuery(itemIndex, getPageSize());
-
-			if (logger.isDebugEnabled()) {
-				logger.debug("SQL used for jumping: [" + jumpToItemSql + "]");
-			}
-
-			if (this.queryProvider.isUsingNamedParameters()) {
-				startAfterValues = namedParameterJdbcTemplate.queryForMap(jumpToItemSql,
-						getParameterMap(parameterValues, null));
-			}
-			else {
-				startAfterValues = getJdbcTemplate().queryForMap(jumpToItemSql,
-						getParameterList(parameterValues, null).toArray());
-			}
-		}
-	}
-
 	private Map<String, Object> getParameterMap(Map<String, Object> values, Map<String, Object> sortKeyValues) {
 		Map<String, Object> parameterMap = new LinkedHashMap<>();
 		if (values != null) {

spring-batch-infrastructure/src/main/java/org/springframework/batch/item/database/JpaPagingItemReader.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2006-2021 the original author or authors.
+ * Copyright 2006-2022 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.
@@ -221,10 +221,6 @@ protected void doReadPage() {
 		} // end if
 	}
 
-	@Override
-	protected void doJumpToPage(int itemIndex) {
-	}
-
 	@Override
 	protected void doClose() throws Exception {
 		entityManager.close();

spring-batch-infrastructure/src/main/java/org/springframework/batch/item/database/PagingQueryProvider.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2006-2012 the original author or authors.
+ * Copyright 2006-2022 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.
@@ -50,18 +50,6 @@ public interface PagingQueryProvider {
 	 */
 	String generateRemainingPagesQuery(int pageSize);
 
-	/**
-	 *
-	 * Generate the query that will provide the jump to item query. The itemIndex provided
-	 * could be in the middle of the page and together with the page size it will be used
-	 * to calculate the last index of the preceding page to be able to retrieve the sort
-	 * key for this row.
-	 * @param itemIndex the index for the next item to be read
-	 * @param pageSize number of rows to read for each page
-	 * @return the generated query
-	 */
-	String generateJumpToItemQuery(int itemIndex, int pageSize);
-
 	/**
 	 * The number of parameters that are declared in the query
 	 * @return number of parameters

spring-batch-infrastructure/src/main/java/org/springframework/batch/item/database/support/AbstractSqlPagingQueryProvider.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2006-2021 the original author or authors.
+ * Copyright 2006-2022 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.
@@ -221,16 +221,6 @@ public void init(DataSource dataSource) throws Exception {
 	@Override
 	public abstract String generateRemainingPagesQuery(int pageSize);
 
-	/**
-	 * Method generating the query string to be used for jumping to a specific item
-	 * position. This method must be implemented in sub classes.
-	 * @param itemIndex the index of the item to jump to
-	 * @param pageSize number of rows to read per page
-	 * @return query string
-	 */
-	@Override
-	public abstract String generateJumpToItemQuery(int itemIndex, int pageSize);
-
 	private String removeKeyWord(String keyWord, String clause) {
 		String temp = clause.trim();
 		int length = keyWord.length();

spring-batch-infrastructure/src/main/java/org/springframework/batch/item/database/support/H2PagingQueryProvider.java

@@ -41,15 +41,4 @@ private String buildLimitClause(int pageSize) {
 		return new StringBuilder().append("FETCH NEXT ").append(pageSize).append(" ROWS ONLY").toString();
 	}
 
-	@Override
-	public String generateJumpToItemQuery(int itemIndex, int pageSize) {
-		int page = itemIndex / pageSize;
-		int offset = (page * pageSize) - 1;
-		offset = offset < 0 ? 0 : offset;
-
-		String limitClause = new StringBuilder().append("OFFSET ").append(offset).append(" ROWS FETCH NEXT 1 ROWS ONLY")
-				.toString();
-		return SqlPagingQueryUtils.generateLimitJumpToQuery(this, limitClause);
-	}
-
 }

spring-batch-infrastructure/src/main/java/org/springframework/batch/item/database/support/HanaPagingQueryProvider.java

@@ -47,13 +47,4 @@ private String buildLimitClause(int pageSize) {
 		return new StringBuilder().append("LIMIT ").append(pageSize).toString();
 	}
 
-	@Override
-	public String generateJumpToItemQuery(int itemIndex, int pageSize) {
-		int page = itemIndex / pageSize;
-		int offset = (page * pageSize) - 1;
-		offset = offset < 0 ? 0 : offset;
-		String limitClause = new StringBuilder().append("LIMIT 1 OFFSET ").append(offset).toString();
-		return SqlPagingQueryUtils.generateLimitJumpToQuery(this, limitClause);
-	}
-
 }

spring-batch-infrastructure/src/main/java/org/springframework/batch/item/database/support/HsqlPagingQueryProvider.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2006-2012 the original author or authors.
+ * Copyright 2006-2022 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.
@@ -48,14 +48,4 @@ private String buildTopClause(int pageSize) {
 		return new StringBuilder().append("TOP ").append(pageSize).toString();
 	}
 
-	@Override
-	public String generateJumpToItemQuery(int itemIndex, int pageSize) {
-		int page = itemIndex / pageSize;
-		int offset = (page * pageSize) - 1;
-		offset = offset < 0 ? 0 : offset;
-
-		String topClause = new StringBuilder().append("LIMIT ").append(offset).append(" 1").toString();
-		return SqlPagingQueryUtils.generateTopJumpToQuery(this, topClause);
-	}
-
 }

spring-batch-infrastructure/src/main/java/org/springframework/batch/item/database/support/MySqlPagingQueryProvider.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2006-2021 the original author or authors.
+ * Copyright 2006-2022 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.
@@ -48,14 +48,4 @@ private String buildLimitClause(int pageSize) {
 		return new StringBuilder().append("LIMIT ").append(pageSize).toString();
 	}
 
-	@Override
-	public String generateJumpToItemQuery(int itemIndex, int pageSize) {
-		int page = itemIndex / pageSize;
-		int offset = (page * pageSize) - 1;
-		offset = offset < 0 ? 0 : offset;
-
-		String limitClause = new StringBuilder().append("LIMIT ").append(offset).append(", 1").toString();
-		return SqlPagingQueryUtils.generateLimitJumpToQuery(this, limitClause);
-	}
-
 }

spring-batch-infrastructure/src/main/java/org/springframework/batch/item/database/support/OraclePagingQueryProvider.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2006-2012 the original author or authors.
+ * Copyright 2006-2022 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.
@@ -16,10 +16,6 @@
 
 package org.springframework.batch.item.database.support;
 
-import java.util.Map;
-
-import org.springframework.batch.item.database.Order;
-
 /**
  * Oracle implementation of a
  * {@link org.springframework.batch.item.database.PagingQueryProvider} using database
@@ -41,29 +37,6 @@ public String generateRemainingPagesQuery(int pageSize) {
 		return SqlPagingQueryUtils.generateRowNumSqlQuery(this, true, buildRowNumClause(pageSize));
 	}
 
-	@Override
-	public String generateJumpToItemQuery(int itemIndex, int pageSize) {
-		int page = itemIndex / pageSize;
-		int offset = (page * pageSize);
-		offset = offset == 0 ? 1 : offset;
-		String sortKeySelect = this.getSortKeySelect();
-		return SqlPagingQueryUtils.generateRowNumSqlQueryWithNesting(this, sortKeySelect, sortKeySelect, false,
-				"TMP_ROW_NUM = " + offset);
-	}
-
-	private String getSortKeySelect() {
-		StringBuilder sql = new StringBuilder();
-		String prefix = "";
-
-		for (Map.Entry<String, Order> sortKey : this.getSortKeys().entrySet()) {
-			sql.append(prefix);
-			prefix = ", ";
-			sql.append(sortKey.getKey());
-		}
-
-		return sql.toString();
-	}
-
 	private String buildRowNumClause(int pageSize) {
 		return new StringBuilder().append("ROWNUM <= ").append(pageSize).toString();
 	}

spring-batch-infrastructure/src/main/java/org/springframework/batch/item/database/support/PostgresPagingQueryProvider.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2006-2021 the original author or authors.
+ * Copyright 2006-2022 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.
@@ -53,13 +53,4 @@ private String buildLimitClause(int pageSize) {
 		return new StringBuilder().append("LIMIT ").append(pageSize).toString();
 	}
 
-	@Override
-	public String generateJumpToItemQuery(int itemIndex, int pageSize) {
-		int page = itemIndex / pageSize;
-		int offset = (page * pageSize) - 1;
-		offset = offset < 0 ? 0 : offset;
-		String limitClause = new StringBuilder().append("LIMIT 1 OFFSET ").append(offset).toString();
-		return SqlPagingQueryUtils.generateLimitJumpToQuery(this, limitClause);
-	}
-
 }

spring-batch-infrastructure/src/main/java/org/springframework/batch/item/database/support/SqlPagingQueryUtils.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2006-2021 the original author or authors.
+ * Copyright 2006-2022 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.
@@ -201,66 +201,6 @@ public static String generateRowNumSqlQuery(AbstractSqlPagingQueryProvider provi
 
 	}
 
-	public static String generateRowNumSqlQueryWithNesting(AbstractSqlPagingQueryProvider provider, String selectClause,
-			boolean remainingPageQuery, String rowNumClause) {
-		return generateRowNumSqlQueryWithNesting(provider, selectClause, selectClause, remainingPageQuery,
-				rowNumClause);
-	}
-
-	public static String generateRowNumSqlQueryWithNesting(AbstractSqlPagingQueryProvider provider,
-			String innerSelectClause, String outerSelectClause, boolean remainingPageQuery, String rowNumClause) {
-
-		StringBuilder sql = new StringBuilder();
-		sql.append("SELECT ").append(outerSelectClause).append(" FROM (SELECT ").append(outerSelectClause).append(", ")
-				.append(StringUtils.hasText(provider.getGroupClause()) ? "MIN(ROWNUM) as TMP_ROW_NUM"
-						: "ROWNUM as TMP_ROW_NUM");
-		sql.append(" FROM (SELECT ").append(innerSelectClause).append(" FROM ").append(provider.getFromClause());
-		buildWhereClause(provider, remainingPageQuery, sql);
-		buildGroupByClause(provider, sql);
-		sql.append(" ORDER BY ").append(buildSortClause(provider));
-		sql.append(")) WHERE ").append(rowNumClause);
-
-		return sql.toString();
-
-	}
-
-	/**
-	 * Generate SQL query string using a LIMIT clause
-	 * @param provider {@link AbstractSqlPagingQueryProvider} providing the implementation
-	 * specifics
-	 * @param limitClause the implementation specific top clause to be used
-	 * @return the generated query
-	 */
-	public static String generateLimitJumpToQuery(AbstractSqlPagingQueryProvider provider, String limitClause) {
-		StringBuilder sql = new StringBuilder();
-		sql.append("SELECT ").append(buildSortKeySelect(provider));
-		sql.append(" FROM ").append(provider.getFromClause());
-		sql.append(provider.getWhereClause() == null ? "" : " WHERE " + provider.getWhereClause());
-		buildGroupByClause(provider, sql);
-		sql.append(" ORDER BY ").append(buildSortClause(provider));
-		sql.append(" " + limitClause);
-
-		return sql.toString();
-	}
-
-	/**
-	 * Generate SQL query string using a TOP clause
-	 * @param provider {@link AbstractSqlPagingQueryProvider} providing the implementation
-	 * specifics
-	 * @param topClause the implementation specific top clause to be used
-	 * @return the generated query
-	 */
-	public static String generateTopJumpToQuery(AbstractSqlPagingQueryProvider provider, String topClause) {
-		StringBuilder sql = new StringBuilder();
-		sql.append("SELECT ").append(topClause).append(" ").append(buildSortKeySelect(provider));
-		sql.append(" FROM ").append(provider.getFromClause());
-		sql.append(provider.getWhereClause() == null ? "" : " WHERE " + provider.getWhereClause());
-		buildGroupByClause(provider, sql);
-		sql.append(" ORDER BY ").append(buildSortClause(provider));
-
-		return sql.toString();
-	}
-
 	/**
 	 * Generates ORDER BY attributes based on the sort keys.
 	 * @param provider the {@link AbstractSqlPagingQueryProvider} to be used for used for
@@ -352,22 +292,6 @@ public static void buildSortConditions(AbstractSqlPagingQueryProvider provider,
 		sql.append(")");
 	}
 
-	private static String buildSortKeySelect(AbstractSqlPagingQueryProvider provider) {
-		StringBuilder select = new StringBuilder();
-
-		String prefix = "";
-
-		for (Map.Entry<String, Order> sortKey : provider.getSortKeys().entrySet()) {
-			select.append(prefix);
-
-			prefix = ", ";
-
-			select.append(sortKey.getKey());
-		}
-
-		return select.toString();
-	}
-
 	private static void buildWhereClause(AbstractSqlPagingQueryProvider provider, boolean remainingPageQuery,
 			StringBuilder sql) {
 		if (remainingPageQuery) {