feat: gradle lockfile support (#1719)

Signed-off-by: Henry Sachs <Henry.Sachs@deutschebahn.com>

syft/pkg/cataloger/java/parse_gradle_lockfile.go

@@ -0,0 +1,63 @@
+package java
+
+import (
+	"bufio"
+	"strings"
+
+	"github.com/anchore/syft/syft/artifact"
+	"github.com/anchore/syft/syft/pkg"
+	"github.com/anchore/syft/syft/pkg/cataloger/generic"
+	"github.com/anchore/syft/syft/source"
+)
+
+const gradleLockfileGlob = "**/gradle.lockfile*"
+
+// Dependency represents a single dependency in the gradle.lockfile file
+type LockfileDependency struct {
+	Group   string
+	Name    string
+	Version string
+}
+
+func parseGradleLockfile(_ source.FileResolver, _ *generic.Environment, reader source.LocationReadCloser) ([]pkg.Package, []artifact.Relationship, error) {
+	var pkgs []pkg.Package
+
+	// Create a new scanner to read the file
+	scanner := bufio.NewScanner(reader)
+
+	// Create slices to hold the dependencies and plugins
+	dependencies := []LockfileDependency{}
+
+	// Loop over all lines in the file
+	for scanner.Scan() {
+		line := scanner.Text()
+
+		// Trim leading and trailing whitespace from the line
+		line = strings.TrimSpace(line)
+
+		groupNameVersion := line
+		groupNameVersion = strings.Split(groupNameVersion, "=")[0]
+		parts := strings.Split(groupNameVersion, ":")
+
+		// we have a version directly specified
+		if len(parts) == 3 {
+			// Create a new Dependency struct and add it to the dependencies slice
+			dep := LockfileDependency{Group: parts[0], Name: parts[1], Version: parts[2]}
+			dependencies = append(dependencies, dep)
+		}
+	}
+	// map the dependencies
+	for _, dep := range dependencies {
+		mappedPkg := pkg.Package{
+			Name:         dep.Name,
+			Version:      dep.Version,
+			Locations:    source.NewLocationSet(reader.Location),
+			Language:     pkg.Java,
+			Type:         pkg.JavaPkg,
+			MetadataType: pkg.JavaMetadataType,
+		}
+		pkgs = append(pkgs, mappedPkg)
+	}
+
+	return pkgs, nil, nil
+}