Slice

Standalone Java library that parses official DTB (Deutscher Tennis Bund) ranking PDFs into typed, validated Java models.

Supported disciplines: Herren · Damen · Junioren · Juniorinnen

Design principle

Lieber laut scheitern als still falsche Daten liefern. (Fail loud rather than silently deliver wrong data.)

Every line that cannot be parsed or validated becomes a ParseIssue — never silently-wrong data.

Requirements

• Java 25
• Maven (the mvnw wrapper is included)

Dependency

Release artifacts are published to Maven Central. SNAPSHOT builds (from main) are available via GitHub Packages.

<dependency>
    <groupId>de.hdawg.slice</groupId>
    <artifactId>slice</artifactId>
    <version>1.0.0-SNAPSHOT</version>
</dependency>

For SNAPSHOT builds, add the GitHub Packages repository to your pom.xml:

<repositories>
    <repository>
        <id>github</id>
        <url>https://maven.pkg.github.com/hwesselmann/slice</url>
    </repository>
</repositories>

Build

./mvnw clean package

Run the test suite:

./mvnw test

Usage

import de.hdawg.tennis.slice.Slice;
import api.de.hdawg.tennis.slice.ParseResult;
import api.de.hdawg.tennis.slice.RankingList;
import api.de.hdawg.tennis.slice.RankingEntry;
import validate.de.hdawg.tennis.slice.ParseMode;

import java.nio.file.Path;

// LENIENT (default): unparseable rows are recorded as ParseIssues and skipped
Slice slice = Slice.builder().build();

        // STRICT: throws IllegalStateException on the first ERROR-severity issue
        Slice strict = Slice.builder().mode(ParseMode.STRICT).build();

        ParseResult result = slice.parse(Path.of("DTB-Herren-Rangliste_20260101.pdf"));

        RankingList ranking = result.list();
System.out.

        println(ranking.discipline());        // HERREN
        System.out.

        println(ranking.stichtag());          // 2025-12-31
        System.out.

        println(ranking.validFrom());         // 2026-01-09
        System.out.

        println(ranking.pointsThreshold());   // 603  (null for juniors)
        System.out.

        println(ranking.birthYears());        // null (YearRange for juniors)

        for(
        RankingEntry entry :ranking.

        entries()){
        System.out.

        printf("%d  %-20s %-15s  %s  %s  %s  %s%n",
               entry.rank(),
        entry.

        lastName(),
        entry.

        firstName(),
        entry.

        dtbId(),
        entry.

        association(),
        entry.

        club(),
        entry.

        score()
    );
            }

// Review any issues (WARNING or ERROR)
            result.

        issues().

        forEach(issue ->
        System.err.

        printf("[%s] page %d — %s%n",issue.severity(),issue.

        page(),issue.

        message())
        );

API

Slice

Method	Description
Slice.builder()	Returns a Builder
builder.mode(ParseMode)	LENIENT (default) or STRICT
slice.parse(Path pdf)	Parses the PDF; returns ParseResult

ParseResult

Field	Type	Description
list()	RankingList	The parsed ranking
issues()	List<ParseIssue>	All warnings and errors encountered

RankingList

Field	Type	Description
discipline()	Discipline	HERREN, DAMEN, JUNIOREN, JUNIORINNEN
stichtag()	LocalDate	Reference date of the ranking (required; LocalDate.MIN if missing and LENIENT)
validFrom()	LocalDate	Validity date; LocalDate.MIN if absent
pointsThreshold()	@Nullable Integer	Points cutoff (Herren/Damen only; null for juniors)
birthYears()	@Nullable YearRange	Birth-year range (juniors only; null for Herren/Damen)
entries()	List<RankingEntry>	Ranked entries, in ranking order

RankingEntry

Field	Type	Description
rank()	int	Rank (1-based)
lastName()	String	Last name
firstName()	String	First name
nationality()	@Nullable String	IOC/DOSB three-letter code (e.g. GER, SUI)
dtbId()	String	8-digit DTB player ID
association()	String	Regional tennis association (VBD) abbreviation
club()	String	Club name
score()	Score	See Score variants below

Score

A sealed interface with four implementations:

Type	Source PDF token	Meaning
Score.Points(BigDecimal value)	e.g. 1234,5	Numeric DTB points
Score.International.ATP	(no token — senior Herren without DTB points)	Ranked via ATP
Score.International.WTA	(no token — senior Damen without DTB points)	Ranked via WTA
Score.ProtectedRanking.INSTANCE	PR	Protected ranking (keeps position without current points)
Score.Projected.INSTANCE	Einst.	Projected entry (placed despite insufficient wins)

The number of seniors at the top of a Herren/Damen list who carry International scores instead of DTB points varies each year and is not validated against a fixed threshold.

Use a pattern-matching switch to handle all cases:

String display = switch (entry.score()) {
    case Score.Points p          -> p.value().toPlainString();
    case Score.International i   -> i.name();           // "ATP" or "WTA"
    case Score.ProtectedRanking r -> "PR";
    case Score.Projected p       -> "Einst.";
};

ParseIssue

Field	Type	Description
severity()	Severity	WARNING or ERROR
page()	int	PDF page number (1-based)
rawLine()	String	The raw text of the offending line
message()	String	Human-readable description (German)

Parse modes

Mode	ERROR issue	WARNING issue
LENIENT	Row/field skipped; issue recorded	Issue recorded; entry included
STRICT	IllegalStateException thrown immediately	Issue recorded; entry included

Nullability

All packages are @NullMarked (JSpecify). Fields that may be absent are annotated @Nullable — there are no sentinel values.