Explore self-contained Java classifier JARs with a statically linked libcuopt

.github/workflows/build.yaml

@@ -64,6 +64,98 @@ jobs:
       date: ${{ inputs.date }}
       sha: ${{ inputs.sha }}
       script: ci/build_cpp.sh
+  # Exploratory (#1817): one self-contained classifier JAR per CUDA major and architecture,
+  # gathered into a single Maven-repository artifact for publishing.
+  java-static-build-matrix:
+    permissions:
+      contents: read
+    uses: rapidsai/shared-workflows/.github/workflows/compute-matrix.yaml@main
+    with:
+      build_type: ${{ inputs.build_type || 'branch' }}
+      matrix_name: conda-cpp-build
+      matrix_filter: 'map(. + {CUDA_MAJOR: (.CUDA_VER | split(".") | .[0])}) | unique_by([.ARCH, .CUDA_MAJOR])'
+
+  java-static-build:
+    needs: [build-details, java-static-build-matrix]
+    permissions:
+      actions: read
+      contents: read
+      id-token: write
+      packages: read
+      pull-requests: read
+    secrets: inherit # zizmor: ignore[secrets-inherit]
+    uses: rapidsai/shared-workflows/.github/workflows/custom-job.yaml@main
+    strategy:
+      fail-fast: false
+      matrix: ${{ fromJSON(needs.java-static-build-matrix.outputs.matrix) }}
+    with:
+      build_type: ${{ inputs.build_type || 'branch' }}
+      branch: ${{ inputs.branch }}
+      date: ${{ inputs.date }}
+      sha: ${{ inputs.sha }}
+      node_type: "cpu16"
+      arch: ${{ matrix.ARCH }}
+      container_image: "rapidsai/ci-conda:26.10-latest"
+      script: "ci/build_java_static.sh"
+      artifact-name: "cuopt_java_${{ matrix.ARCH }}_cu${{ matrix.CUDA_MAJOR }}"
+      file_to_upload: "java/cuopt/classifier-jars/"
+
+  # Combines every classifier into one Maven-repository-layout artifact, which is the form a
+  # publishing workflow consumes. See rapidsai/build-infra#379.
+  # Runs the full Java suite against each classifier JAR on a GPU, with no libcuopt installed,
+  # so a JAR that loads but computes wrong answers fails here rather than at a user.
+  java-static-test:
+    needs: [java-static-build, java-static-build-matrix]
+    permissions:
+      actions: read
+      contents: read
+      id-token: write
+      packages: read
+      pull-requests: read
+    secrets: inherit # zizmor: ignore[secrets-inherit]
+    uses: rapidsai/shared-workflows/.github/workflows/custom-job.yaml@main
+    strategy:
+      fail-fast: false
+      matrix: ${{ fromJSON(needs.java-static-build-matrix.outputs.matrix) }}
+    with:
+      build_type: ${{ inputs.build_type || 'branch' }}
+      branch: ${{ inputs.branch }}
+      date: ${{ inputs.date }}
+      sha: ${{ inputs.sha }}
+      node_type: "gpu-l4-latest-1"
+      arch: ${{ matrix.ARCH }}
+      container_image: "rapidsai/ci-conda:26.10-latest"
+      script: "ci/test_java_static.sh"
+
+  java-static-gather:
+    needs: [java-static-build]
+    runs-on: linux-amd64-cpu4
+    permissions:
+      contents: read
+    steps:
+      - name: Checkout code repo
+        uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5 # v4.3.1
+        with:
+          ref: ${{ inputs.sha }}
+          persist-credentials: false
+      - name: Download per-classifier JAR artifacts
+        uses: actions/download-artifact@d3f86a106a0bac45b974a628896c90dbdf5c8093 # v4.3.0
+        with:
+          pattern: cuopt_java_*
+          path: ${{ runner.temp }}/jars
+          merge-multiple: true
+      - name: Assemble Maven repository layout
+        run: |
+          ./java/cuopt/ci/assemble_maven_repo.sh \
+            --jars-dir "${RUNNER_TEMP}/jars" \
+            --output-dir "${RUNNER_TEMP}/maven-repo"
+      - name: Upload combined Maven repository artifact
+        uses: actions/upload-artifact@ea165f8d65b6e75b540449e92b4886f43607fa02 # v4.6.2
+        with:
+          name: cuopt_java_maven_repo
+          path: ${{ runner.temp }}/maven-repo
+          if-no-files-found: error
+
   java-build:
     needs: cpp-build
     permissions:

.github/workflows/pr.yaml

@@ -24,6 +24,10 @@ jobs:
       - conda-cpp-build
       - conda-cpp-tests
       - java-build
+      - java-static-build-matrix
+      - java-static-build
+      - java-static-test
+      - java-static-gather
       - conda-python-build
       - conda-python-tests
       - docs-build
@@ -113,6 +117,7 @@ jobs:
           - '!SECURITY.md'
           - '!ci/build_wheel*.sh'
           - '!ci/build_java.sh'
+          - '!ci/build_java_static.sh'
           - '!ci/check_style.sh'
           - '!ci/docker/**'
           - '!ci/release/**'
@@ -178,6 +183,7 @@ jobs:
           - '!agents/**'
           - '!ci/build_docs.sh'
           - '!ci/build_java.sh'
+          - '!ci/build_java_static.sh'
           - '!ci/build_python.sh'
           - '!ci/build_wheel*.sh'
           - '!ci/check_style.sh'
@@ -213,6 +219,7 @@ jobs:
         test_java:
           - 'java/**'
           - 'ci/build_java.sh'
+          - 'ci/build_java_static.sh'
           - 'ci/test_java.sh'
           - 'dependencies.yaml'
           - '.github/workflows/pr.yaml'
@@ -262,6 +269,7 @@ jobs:
           - '!agents/**'
           - '!ci/build_docs.sh'
           - '!ci/build_java.sh'
+          - '!ci/build_java_static.sh'
           - '!ci/build_wheel*.sh'
           - '!ci/check_style.sh'
           - '!ci/docker/**'
@@ -337,6 +345,7 @@ jobs:
           - '!ci/build_docs.sh'
           - '!ci/build_python.sh'
           - '!ci/build_java.sh'
+          - '!ci/build_java_static.sh'
           - '!ci/check_style.sh'
           - '!ci/docker/**'
           - '!ci/release/**'
@@ -477,6 +486,97 @@ jobs:
       artifact-name: "cuopt_docs"
       container_image: "rapidsai/ci-conda:26.10-latest"
       script: "ci/build_docs.sh"
+  # Exploratory (#1817): one self-contained classifier JAR per CUDA major and architecture,
+  # gathered into a single Maven-repository artifact. Compiles libcuopt from source, so it does
+  # not need conda-cpp-build.
+  java-static-build-matrix:
+    needs: changed-files
+    permissions:
+      contents: read
+    uses: rapidsai/shared-workflows/.github/workflows/compute-matrix.yaml@main
+    if: >-
+      fromJSON(needs.changed-files.outputs.changed_file_groups).test_java ||
+      fromJSON(needs.changed-files.outputs.changed_file_groups).test_cpp
+    with:
+      build_type: pull-request
+      matrix_name: conda-cpp-build
+      matrix_filter: 'map(. + {CUDA_MAJOR: (.CUDA_VER | split(".") | .[0])}) | unique_by([.ARCH, .CUDA_MAJOR])'
+
+  java-static-build:
+    needs: [java-static-build-matrix, changed-files]
+    permissions:
+      actions: read
+      contents: read
+      id-token: write
+      packages: read
+      pull-requests: read
+    secrets: inherit # zizmor: ignore[secrets-inherit]
+    uses: rapidsai/shared-workflows/.github/workflows/custom-job.yaml@main
+    strategy:
+      fail-fast: false
+      matrix: ${{ fromJSON(needs.java-static-build-matrix.outputs.matrix) }}
+    if: >-
+      fromJSON(needs.changed-files.outputs.changed_file_groups).test_java ||
+      fromJSON(needs.changed-files.outputs.changed_file_groups).test_cpp
+    with:
+      build_type: pull-request
+      node_type: "cpu16"
+      arch: ${{ matrix.ARCH }}
+      container_image: "rapidsai/ci-conda:26.10-latest"
+      script: "ci/build_java_static.sh"
+      artifact-name: "cuopt_java_${{ matrix.ARCH }}_cu${{ matrix.CUDA_MAJOR }}"
+      file_to_upload: "java/cuopt/classifier-jars/"
+
+  # Runs the full Java suite against each classifier JAR on a GPU, with no libcuopt installed,
+  # so a JAR that loads but computes wrong answers fails here rather than at a user.
+  java-static-test:
+    needs: [java-static-build, java-static-build-matrix]
+    permissions:
+      actions: read
+      contents: read
+      id-token: write
+      packages: read
+      pull-requests: read
+    secrets: inherit # zizmor: ignore[secrets-inherit]
+    uses: rapidsai/shared-workflows/.github/workflows/custom-job.yaml@main
+    strategy:
+      fail-fast: false
+      matrix: ${{ fromJSON(needs.java-static-build-matrix.outputs.matrix) }}
+    with:
+      build_type: pull-request
+      node_type: "gpu-l4-latest-1"
+      arch: ${{ matrix.ARCH }}
+      container_image: "rapidsai/ci-conda:26.10-latest"
+      script: "ci/test_java_static.sh"
+
+  java-static-gather:
+    needs: [java-static-build]
+    runs-on: linux-amd64-cpu4
+    permissions:
+      contents: read
+    steps:
+      - name: Checkout code repo
+        uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5 # v4.3.1
+        with:
+          persist-credentials: false
+      - name: Download per-classifier JAR artifacts
+        uses: actions/download-artifact@d3f86a106a0bac45b974a628896c90dbdf5c8093 # v4.3.0
+        with:
+          pattern: cuopt_java_*
+          path: ${{ runner.temp }}/jars
+          merge-multiple: true
+      - name: Assemble Maven repository layout
+        run: |
+          ./java/cuopt/ci/assemble_maven_repo.sh \
+            --jars-dir "${RUNNER_TEMP}/jars" \
+            --output-dir "${RUNNER_TEMP}/maven-repo"
+      - name: Upload combined Maven repository artifact
+        uses: actions/upload-artifact@ea165f8d65b6e75b540449e92b4886f43607fa02 # v4.6.2
+        with:
+          name: cuopt_java_maven_repo
+          path: ${{ runner.temp }}/maven-repo
+          if-no-files-found: error
+
   java-build:
     needs: [conda-cpp-build, changed-files]
     permissions:

ci/build_java_static.sh

@@ -0,0 +1,70 @@
+#!/bin/bash
+
+# SPDX-FileCopyrightText: Copyright (c) 2026, NVIDIA CORPORATION & AFFILIATES. All rights reserved.
+# SPDX-License-Identifier: Apache-2.0
+
+# Builds a self-contained Java classifier JAR and checks that it is actually self-contained.
+#
+# Unlike ci/build_java.sh, which installs a prebuilt libcuopt and links it as a shared library,
+# this compiles libcuopt from source as a static archive and embeds it, so the JAR is the only
+# thing a consumer installs. See #1817.
+
+set -euo pipefail
+
+if [[ -e /opt/conda/etc/profile.d/conda.sh ]]; then
+  . /opt/conda/etc/profile.d/conda.sh
+fi
+
+rapids-logger "Configuring conda strict channel priority"
+conda config --set channel_priority strict
+
+rapids-logger "Generating Java static build dependencies"
+ENV_YAML_DIR=$(mktemp -d)
+rapids-dependency-file-generator \
+  --output conda \
+  --file-key java_static \
+  --matrix "cuda=${RAPIDS_CUDA_VERSION%.*};arch=$(arch)" | tee "${ENV_YAML_DIR}/env.yaml"
+
+rapids-mamba-retry env create --yes -f "${ENV_YAML_DIR}/env.yaml" -n java_static
+
+# Temporarily allow unbound variables for conda activation.
+set +u
+conda activate java_static
+set -u
+
+rapids-print-env
+
+export CUOPT_PREFIX="${CONDA_PREFIX}"
+STATIC_BUILD_DIR="${PWD}/cpp/build-static"
+JNI_BUILD_DIR="${PWD}/java/cuopt/build/native-static"
+JAR_OUTPUT_DIR="${PWD}/java/cuopt/classifier-jars"
+
+rapids-logger "Building the scoped static libcuopt"
+BUILD_DIR="${STATIC_BUILD_DIR}" bash java/cuopt/ci/build_static_libcuopt.sh
+
+rapids-logger "Linking libcuopt into cuopt_jni"
+cmake -S java/cuopt -B "${JNI_BUILD_DIR}" -GNinja \
+  -DCMAKE_BUILD_TYPE=Release \
+  -DCUOPT_PREFIX="${CUOPT_PREFIX}" \
+  -DCUOPT_STATIC_BUILD_DIR="${STATIC_BUILD_DIR}" \
+  -DCUOPT_EXTRA_INCLUDE_DIRS="${PWD}/cpp/include;${STATIC_BUILD_DIR}/include"
+cmake --build "${JNI_BUILD_DIR}" --parallel "${PARALLEL_LEVEL:-$(nproc)}"
+
+rapids-logger "Packaging the classifier JAR"
+bash java/cuopt/ci/build_cuopt_java_jar.sh \
+  --native-lib "${JNI_BUILD_DIR}/libcuopt_jni.so" \
+  --cuda-version "${RAPIDS_CUDA_VERSION}" \
+  --output-dir "${JAR_OUTPUT_DIR}"
+
+# The JAR looking fine on this machine proves nothing: the build environment supplies every
+# dependency by construction. This resolves them the way a consumer's machine would.
+rapids-logger "Verifying the JAR is self-contained"
+CLASSIFIER_JAR=$(find "${JAR_OUTPUT_DIR}" -name 'cuopt-*.jar' \
+  ! -name '*-sources.jar' ! -name '*-javadoc.jar' -print -quit)
+bash java/cuopt/ci/verify_jar_dependencies.sh --jar "${CLASSIFIER_JAR}"
+
+# The gather job combines the classifier directories from every matrix entry into one Maven
+# repository layout; this job uploads its own directory as-is.
+rapids-logger "Result"
+du -h "${CLASSIFIER_JAR}" | sed 's/^/  /'
+find "${JAR_OUTPUT_DIR}" -type f | sed "s|^${JAR_OUTPUT_DIR}/|  |" | sort

ci/test_java_static.sh

@@ -0,0 +1,79 @@
+#!/bin/bash
+
+# SPDX-FileCopyrightText: Copyright (c) 2026, NVIDIA CORPORATION & AFFILIATES. All rights reserved.
+# SPDX-License-Identifier: Apache-2.0
+
+# Runs the Java test suite against an already-packaged classifier JAR, on a GPU, with no
+# libcuopt installed. See #1817.
+#
+# ci/build_java_static.sh checks the JAR's dependencies statically; this is the other half,
+# that the libraries it carries actually load and produce correct answers.
+#
+# Activates -Ppackaged-jar-tests so main compilation is skipped and the JAR supplies the classes
+# and the native libraries. PackagedJarOriginCheck then asserts that is genuinely where they came
+# from, so a stray target/classes cannot make this pass while testing the wrong thing.
+#
+# CUOPT_JAVA_JAR may be set to a classifier JAR to skip the download and test it directly.
+
+set -euo pipefail
+
+REPO_ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
+# shellcheck source=java/cuopt/ci/java_classifier.sh
+. "${REPO_ROOT}/java/cuopt/ci/java_classifier.sh"
+# shellcheck source=java/cuopt/scripts/maven.sh
+. "${REPO_ROOT}/java/cuopt/scripts/maven.sh"
+cuopt_maven_args
+
+if [[ -e /opt/conda/etc/profile.d/conda.sh ]]; then
+  . /opt/conda/etc/profile.d/conda.sh
+fi
+
+if [[ -z "${CUOPT_JAVA_JAR:-}" ]]; then
+  case "$(arch)" in
+    x86_64) JOB_ARCH=amd64 ;;
+    aarch64) JOB_ARCH=arm64 ;;
+    *) echo "unsupported architecture $(arch)" >&2; exit 1 ;;
+  esac
+  ARTIFACT="cuopt_java_${JOB_ARCH}_cu${RAPIDS_CUDA_VERSION%%.*}"
+  rapids-logger "Downloading ${ARTIFACT}"
+  JAVA_PKG="$(rapids-download-from-github "${ARTIFACT}")"
+  CUOPT_JAVA_JAR="$(cuopt_java_resolve_artifact_jar "${JAVA_PKG}")"
+fi
+rapids-logger "Testing $(basename "${CUOPT_JAVA_JAR}")"
+
+# A JDK, Maven and the CUDA runtime only. Installing libcuopt would defeat the test, since the
+# JAR is supposed to carry its own copy.
+rapids-logger "Creating a consumer-like environment"
+ENV_YAML_DIR=$(mktemp -d)
+cat > "${ENV_YAML_DIR}/env.yaml" << EOF
+name: java_static_test
+channels:
+  - conda-forge
+dependencies:
+  - openjdk=11.*
+  - maven
+  - cuda-version=${RAPIDS_CUDA_VERSION%.*}
+  - libcublas
+  - libcusparse
+EOF
+rapids-mamba-retry env create --yes -f "${ENV_YAML_DIR}/env.yaml" -n java_static_test
+
+set +u
+conda activate java_static_test
+set -u
+
+if [[ -e "${CONDA_PREFIX}/lib/libcuopt.so" ]]; then
+  echo "ERROR: libcuopt.so is present in the test environment, so passing here would not show" >&2
+  echo "       that the JAR is self-contained." >&2
+  exit 1
+fi
+
+rapids-print-env
+nvidia-smi
+
+rapids-logger "Running the suite against the packaged JAR"
+cuopt_mvn -B -f "${REPO_ROOT}/java/cuopt/pom.xml" test \
+  -Ppackaged-jar-tests \
+  "-Dcuopt.jar.path=${CUOPT_JAVA_JAR}"
+
+rapids-logger "Classifier JAR verified end to end"