org.fluentjdbc.DbContextSqlBuilder Maven / Gradle / Ivy

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package org.fluentjdbc;

import javax.annotation.CheckReturnValue;
import javax.annotation.Nonnull;
import java.sql.Connection;
import java.util.Collection;
import java.util.List;
import java.util.Optional;
import java.util.stream.Stream;

/**
 * Used to construct SQL SELECT statements in a flexible way with {@link #where(String, Object)}
 * clauses, {@link #select(String...)} column names, {@link #from(String)} table statement,
 * {@link #groupBy(String...)}, {@link #orderBy(String)} and {@link #skipAndLimit(int, int)}.
 *
 * Example:
 *
 *  * new DbContextSqlBuilder(dbContext)
 *      .select("first_name", "last_name")
 *      .select("p.id")
 *      .from("person p full join organizations o")
 *      .where("organization_sector", sector)
 *      .limit(100)
 *      .list(row -> List.of(row.getString("first_name"), row.getString("last_name"), row.getUUID("p.id"));
 * 
 *
 */
public class DbContextSqlBuilder implements DbContextListableSelect {

    private final DatabaseSqlBuilder builder;
    private final DbContext dbContext;

    public DbContextSqlBuilder(DbContext dbContext) {
        this.dbContext = dbContext;
        builder = new DatabaseSqlBuilder(dbContext.getStatementFactory());
    }

    /**
     * Implemented as return this for compatibility purposes
     */
    @Override
    public DbContextSqlBuilder query() {
        return this;
    }

    /**
     * Add the arguments to the column list for the SELECT column, column... statement
     */
    @CheckReturnValue
    public DbContextSqlBuilder select(String... columns) {
        return query(builder.select(columns));
    }

    /**
     * Replace the from part of the SELECT ... FROM fromStatement in the select statement
     */
    @CheckReturnValue
    public DbContextSqlBuilder from(String fromStatement) {
        return query(builder.from(fromStatement));
    }

    /**
     * Adds the expression to the WHERE-clause and all the values to the parameter list.
     * E.g. whereExpressionWithParameterList("created_at between ? and ?", List.of(earliestDate, latestDate))
     */
    @Override
    public DbContextSqlBuilder whereExpressionWithParameterList(String expression, Collection parameters) {
        return query(builder.whereExpressionWithParameterList(expression, parameters));
    }

    /**
     * Add the arguments to the column list for the SELECT ... FROM ... ... GROUP BY groupByStatement statement
     */
    @CheckReturnValue
    public DbContextSqlBuilder groupBy(String... groupByStatement) {
        return query(builder.groupBy(groupByStatement));
    }

    /**
     * Adds ORDER BY ... clause to the SELECT statement
     */
    @Override
    public DbContextSqlBuilder orderBy(String orderByClause) {
        return query(builder.orderBy(orderByClause));
    }

    /**
     * If you haven't called {@link #orderBy}, the results of {@link DatabaseListableQueryBuilder#list}
     * will be unpredictable. Call unordered() if you are okay with this.
     */
    @CheckReturnValue
    public DbContextSqlBuilder unordered() {
        return query(builder.unordered());
    }

    /**
     * Adds OFFSET ... ROWS FETCH ... ROWS ONLY clause to the SELECT
     * statement. FETCH FIRST was introduced in
     * SQL:2008
     * and is supported by Postgresql 8.4, Oracle 12c, IBM DB2, HSQLDB, H2, and SQL Server 2012.
     */
    @Override
    public DbContextSqlBuilder skipAndLimit(int offset, int rowCount) {
        return query(builder.skipAndLimit(offset, rowCount));
    }

    /**
     * Execute the query and map each return value over the {@link DatabaseResult.RowMapper} function to return a stream. Example:
     *      *     table.where("status", status).stream(row -> row.getInstant("created_at"))
     * 
     */
    @Override
    public