#794: `BuchungssatzImpl.java`

projectforge-business/src/main/java/org/projectforge/reporting/impl/BuchungssatzImpl.java Adapter, projectforge-business/src/main/java/org/projectforge/reporting/impl/BuchungssatzImpl.java 143 lines · 90 code · 27 comments · 26 blank

Adapter Pattern for BuchungssatzDO

Proxy/adapter for BuchungssatzDO — the JPA entity representing an accounting entry in org.projectforge.business.fibu.kost. Implements the Buchungssatz reporting interface from org.projectforge.reporting. Javadoc: "Proxy for BuchungssatzDO".

This is the classic Adapter pattern: a JPA entity cannot directly implement a reporting interface (they live in separate modules with different dependency graphs), so a wrapper delegates all calls to the DO. At 143 lines, it is the largest Impl wrapper in the reporting package.

In its constructor, it accepts a BuchungssatzDO, extracts related objects (Konto, GegenKonto, Kost1, Kost2), and wraps each into its corresponding Impl class: KontoImpl (#795), Kost1Impl, Kost2Impl. All fields are cached as final — created once during construction and never recomputed.

Why not `BuchungssatzDO implements Buchungssatz`?

The JPA entity lives in the projectforge-business module, while the reporting interface is consumed by the financial reporting module. A direct dependency would create a circular dependency. The Adapter solves this: the DO knows nothing about reporting, and reporting obtains data through the wrapper. Additionally, the Impl can transform data (e.g. getFormattedMonth() calling StringHelper.format2DigitNumber()) without polluting the DO with reporting-specific formatting logic.

Method Delegation

Every getter simply delegates to the underlying BuchungssatzDO:

Method	Returns	Source
`getId()`	`Long`	Direct delegate
`getBeleg()`	Document number	Direct delegate
`getBetrag()`	`BigDecimal` amount	Direct delegate
`getComment()`	String	Direct delegate
`getDatum()`	`LocalDate`	Direct delegate
`getGegenKonto()`	`Konto`	Cached Impl proxy
`getKonto()`	`Konto`	Cached Impl proxy
`getKost1()`	`Kost1`	Cached Impl proxy
`getKost2()`	`Kost2`	Cached Impl proxy
`getMenge()`	Quantity string	Direct delegate
`getMonth()`	`Integer`	Direct delegate
`getFormattedMonth()`	2-digit string	Formatted via `StringHelper`
`getSatznr()`	`Integer`	Direct delegate
`getSh()`	`SHType` (debit/credit)	Direct delegate
`getText()`	String	Direct delegate
`getYear()`	`Integer`	Direct delegate

Type Migration History

The ID was migrated from Integer to Long in commit 4c04cfd65. Date fields use java.time.LocalDate (migrated from java.util.Date in 78b436d9e).

Git History

868d6abb7 2025 -> 2026
63081666f Source file headers: 2024-> 2025.
4c04cfd65 MAJOR-CHANGE! Migration of integer id's to Long id's (including fk's etc.)
b6092df09 Copyright 2023 -> 2024
ab45d51fa Copyright 2001-2022 -> 2001-2023.
5f7ef41b8 Copyright 2021 -> 2022
ceb63e8a1 Source code header: (C) 2001-2021.
a6a7aece4 Optimize Imports
78b436d9e Replace instances of java.util.date and java.sql.Date with java.time.LocalDate
7c79f1922 Copyright of source header -> 2020.