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A Java library used to execute JDBC statements and build SQL

There is a newer version: 0.5.3

package org.fluentjdbc;

import javax.annotation.Nonnull;
import java.sql.PreparedStatement;
import java.util.function.Function;

/**
 * Fluently generate a UPDATE ... statement for a list of objects. Create with a list of object
 * and use {@link #setField(String, Function)} to pass in a function that will be called for each object
 * in the list to create the SET field = ? value and {@link #where(String, Function)}
 * which will be called for each object to create the WHERE field = ? value.
 *
 * Example:
 *
 *  *     public void saveAll(List<TagType> tagTypes) {
 *         tagTypesTable.bulkUpdate(tagTypes)
 *              .where("id", TagType::getId)
 *              .setField("name", TagType::getName)
 *              .execute();
 *     }
 * 
 */
public class DbContextBulkUpdateBuilder implements
        DatabaseBulkQueryable>, DatabaseBulkUpdatable> {

    private final DbContextTable table;
    private final DatabaseBulkUpdateBuilder builder;

    public DbContextBulkUpdateBuilder(@Nonnull DbContextTable table, DatabaseBulkUpdateBuilder builder) {
        this.table = table;
        this.builder = builder;
    }

    /**
     * Adds a function that will be called for each object to get the value for
     * {@link PreparedStatement#setObject(int, Object)} for each row in the bulk update
     * to extract the values for the WHERE fieldName = ? clause
     */
    @Override
    public DbContextBulkUpdateBuilder where(String field, Function value) {
        //noinspection ResultOfMethodCallIgnored
        builder.where(field, value);
        return this;
    }

    /**
     * Adds a function that will be called for each object to get the value for
     * {@link PreparedStatement#setObject(int, Object)} for each row in the bulk update
     * to extract the values for the SET fieldName = ? clause
     */
    @Override
    public DbContextBulkUpdateBuilder setField(String fieldName, Function transformer) {
        //noinspection ResultOfMethodCallIgnored
        builder.setField(fieldName, transformer);
        return this;
    }

    /**
     * Executes UPDATE table SET field = ?, ... WHERE field = ? AND ...
     * and calls {@link PreparedStatement#addBatch()} for each row
     *
     * @return the count of rows that were updated
     */
    public int execute() {
        return builder.execute(table.getConnection());
    }

}