jvpp: add support for unions (VPP-1322)

[vpp.git] / src / vpp-api / java / jvpp / gen / jvppgen / unions_gen.py

diff --git a/src/vpp-api/java/jvpp/gen/jvppgen/unions_gen.py b/src/vpp-api/java/jvpp/gen/jvppgen/unions_gen.py
new file mode 100755 (executable)
index 0000000..f67704f
--- /dev/null
+++ b/src/vpp-api/java/jvpp/gen/jvppgen/unions_gen.py
@@ -0,0 +1,98 @@
+#!/usr/bin/env python2
+#
+# Copyright (c) 2018 Cisco and/or its affiliates.
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at:
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from string import Template
+
+from jvpp_common_gen import generate_hash_code, generate_equals, generate_to_string, generate_fields
+from jvpp_model import Union
+
+
+def generate_unions(work_dir, model, logger):
+    logger.debug("Generating unions for %s " % model.json_api_files)
+
+    for t in model.types:
+        if not isinstance(t, Union):
+            continue
+        logger.debug("Generating DTO for union %s", t)
+        java_union_name = t.java_name
+        fields = t.fields
+        type_class = _UNION_TEMPLATE.substitute(
+            plugin_package=model.plugin_package,
+            c_type_name=t.name,
+            json_filename=model.json_api_files,
+            json_definition=t.doc,
+            java_union_name=java_union_name,
+            fields=generate_fields(fields, access_modifier="private"),
+            constructors=_generate_constructors(java_union_name, fields),
+            getters=_generate_getters(fields),
+            hash_code=generate_hash_code(fields),
+            equals=generate_equals(java_union_name, fields),
+            to_string=generate_to_string(java_union_name, fields)
+        )
+        with open("%s/%s.java" % (work_dir, java_union_name), "w") as f:
+            f.write(type_class)
+
+_UNION_TEMPLATE = Template("""
+package ${plugin_package}.types;
+
+/**
+ * <p>This class represents ${c_type_name} union definition.
+ * <br>It was generated by unions_gen.py based on ${json_filename}:
+ * <pre>
+${json_definition}
+ * </pre>
+ */
+public class ${java_union_name} {
+    private final int _activeMember;
+${fields}
+    private ${java_union_name}() {
+        // Constructor for JNI usage. All members can be read.
+        _activeMember = -1;
+    }
+${constructors}
+${getters}
+${hash_code}
+${equals}
+${to_string}
+}
+""")
+
+
+def _generate_constructors(union_name, fields):
+    return "".join(
+        _CONSTRUCTOR_TEMPLATE
+        .substitute(union_name=union_name,
+                    field_type=f.type.java_name_fqn,
+                    field_name=f.java_name,
+                    field_index=i) for i, f in enumerate(fields))
+
+_CONSTRUCTOR_TEMPLATE = Template("""
+    public ${union_name}(${field_type} ${field_name}) {
+        this.${field_name} = java.util.Objects.requireNonNull(${field_name}, "${field_name} should not be null");
+        _activeMember = $field_index;
+    }""")
+
+
+def _generate_getters(fields):
+    return "".join(_GETTER_TEMPLATE.substitute(
+        type=f.type.java_name_fqn,
+        getter_name=f.java_name_upper,
+        field_name=f.java_name
+    ) for f in fields)
+
+_GETTER_TEMPLATE = Template("""
+    public ${type} get${getter_name}() {
+        return ${field_name};
+    }""")