THRIFT-222. java: Better exposure if __isset in beans style

- Generate an isSet method for each field to test its set-ness.
- Generate a generic isSet method that checks by field id.


git-svn-id: https://svn.apache.org/repos/asf/incubator/thrift/trunk@731722 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/compiler/cpp/src/generate/t_java_generator.cc b/compiler/cpp/src/generate/t_java_generator.cc
index a49c0a8..4a9dfc9 100644
--- a/compiler/cpp/src/generate/t_java_generator.cc
+++ b/compiler/cpp/src/generate/t_java_generator.cc
@@ -82,6 +82,7 @@
   void generate_reflection_setters(std::ostringstream& out, t_type* type, std::string field_name, std::string cap_name);
   void generate_reflection_getters(std::ostringstream& out, t_type* type, std::string field_name, std::string cap_name);
   void generate_generic_field_getters_setters(std::ofstream& out, t_struct* tstruct);
+  void generate_generic_isset_method(std::ofstream& out, t_struct* tstruct);
   void generate_java_bean_boilerplate(std::ofstream& out, t_struct* tstruct);
 
   void generate_function_helpers(t_function* tfunction);
@@ -706,6 +707,7 @@
   if (bean_style_) {
     generate_java_bean_boilerplate(out, tstruct);
     generate_generic_field_getters_setters(out, tstruct);
+    generate_generic_isset_method(out, tstruct);
   }
 
   generate_java_struct_equality(out, tstruct);
@@ -1203,7 +1205,33 @@
   indent(out) << "}" << endl << endl;
 }
 
+// Creates a generic isSet method that takes the field number as argument
+void t_java_generator::generate_generic_isset_method(std::ofstream& out, t_struct* tstruct){
+  const vector<t_field*>& fields = tstruct->get_members();
+  vector<t_field*>::const_iterator f_iter;
 
+  // create the isSet method
+  indent(out) << "// Returns true if field corresponding to fieldID is set (has been asigned a value) and false otherwise" << endl;
+  indent(out) << "public boolean isSet(int fieldID) {" << endl;
+  indent_up();
+  indent(out) << "switch (fieldID) {" << endl;
+
+  for (f_iter = fields.begin(); f_iter != fields.end(); ++f_iter) {
+    t_field* field = *f_iter;
+    indent(out) << "case " << upcase_string(field->get_name()) << ":" << endl;
+    indent_up();
+    indent(out) << "return this.__isset." << field->get_name() << ";" << endl;
+    indent_down();
+  }
+
+  indent(out) << "default:" << endl;
+  indent(out) << "  throw new IllegalArgumentException(\"Field \" + fieldID + \" doesn't exist!\");" << endl;
+
+  indent(out) << "}" << endl;
+
+  indent_down();
+  indent(out) << "}" << endl << endl;
+}
 
 /**
  * Generates a set of Java Bean boilerplate functions (setters, getters, etc.)
@@ -1334,6 +1362,14 @@
     indent(out) << "this.__isset." << field_name << " = false;" << endl;
     indent_down();
     indent(out) << "}" << endl << endl;
+
+    // isSet method
+    indent(out) << "// Returns true if field " << field_name << " is set (has been asigned a value) and false otherwise" << endl;
+    indent(out) << "public boolean is" << get_cap_name("set") << cap_name << "() {" << endl;
+    indent_up();
+    indent(out) << "return this.__isset." << field_name << ";" << endl;
+    indent_down();
+    indent(out) << "}" << endl << endl;
   }
 }
 
diff --git a/test/JavaBeansTest.thrift b/test/JavaBeansTest.thrift
new file mode 100644
index 0000000..0b4b160
--- /dev/null
+++ b/test/JavaBeansTest.thrift
@@ -0,0 +1,15 @@
+namespace java thrift.test
+
+struct OneOfEachBeans {
+  1: bool boolean_field,
+  2: byte a_bite,
+  3: i16 integer16,
+  4: i32 integer32,
+  5: i64 integer64,
+  6: double double_precision,
+  7: string some_characters,
+  8: binary base64,
+  9: list<byte> byte_list,
+  10: list<i16> i16_list,
+  11: list<i64> i64_list
+}
diff --git a/test/java/build.xml b/test/java/build.xml
index 1ed1ff1..0860d9c 100644
--- a/test/java/build.xml
+++ b/test/java/build.xml
@@ -4,6 +4,7 @@
 
   <property name="src" location="src" />
   <property name="gen" location="gen-java" />
+  <property name="genbean" location="gen-javabean" />
   <property name="build" location="build" />
   <property name="cpath" location="../../lib/java/libthrift.jar:/usr/share/java/commons-lang-2.3.jar" />
   <property name="testjar" location="thrifttest.jar" />
@@ -24,12 +25,13 @@
       <arg line="--gen java:hashcode ../OptionalRequiredTest.thrift" />
     </exec>
     <exec executable="../../compiler/cpp/thrift">
-      <arg line="--gen java ../DebugProtoTest.thrift" />
+      <arg line="--gen java:beans,nocamel ../JavaBeansTest.thrift" />
     </exec>
   </target>
 
   <target name="compileonly">
     <javac debug="true" srcdir="${gen}" destdir="${build}" classpath="${cpath}" />
+    <javac debug="true" srcdir="${genbean}" destdir="${build}" classpath="${cpath}" />
     <javac debug="true" srcdir="${src}" destdir="${build}" classpath="${cpath}:${gen}" />
   </target>
 
@@ -48,10 +50,13 @@
       classpath="${cpath}:${testjar}:${gen}" failonerror="true" />
     <java classname="com.facebook.thrift.test.DeepCopyTest"
       classpath="${cpath}:${testjar}:${gen}" failonerror="true" />
+    <java classname="com.facebook.thrift.test.JavaBeansTest"
+      classpath="${cpath}:${testjar}:${gen}" failonerror="true" />
   </target>
 
   <target name="clean">
     <delete dir="gen-java" />
+    <delete dir="gen-javabean" />
     <delete dir="${build}" />
     <delete file="thrifttest.jar" />
   </target>
diff --git a/test/java/src/JavaBeansTest.java b/test/java/src/JavaBeansTest.java
new file mode 100644
index 0000000..f1d70a3
--- /dev/null
+++ b/test/java/src/JavaBeansTest.java
@@ -0,0 +1,91 @@
+package com.facebook.thrift.test;
+
+import java.util.LinkedList;
+import thrift.test.OneOfEachBeans;
+
+public class JavaBeansTest {
+  public static void main(String[] args) throws Exception {
+    // Test isSet methods
+    OneOfEachBeans ooe = new OneOfEachBeans();
+
+    // Nothing should be set
+    if (ooe.is_set_a_bite())
+      throw new RuntimeException("isSet method error: unset field returned as set!");
+    if (ooe.is_set_base64())
+      throw new RuntimeException("isSet method error: unset field returned as set!");
+    if (ooe.is_set_byte_list())
+      throw new RuntimeException("isSet method error: unset field returned as set!");
+    if (ooe.is_set_double_precision())
+      throw new RuntimeException("isSet method error: unset field returned as set!");
+    if (ooe.is_set_i16_list())
+      throw new RuntimeException("isSet method error: unset field returned as set!");
+    if (ooe.is_set_i64_list())
+      throw new RuntimeException("isSet method error: unset field returned as set!");
+    if (ooe.is_set_boolean_field())
+      throw new RuntimeException("isSet method error: unset field returned as set!");
+    if (ooe.is_set_integer16())
+      throw new RuntimeException("isSet method error: unset field returned as set!");
+    if (ooe.is_set_integer32())
+      throw new RuntimeException("isSet method error: unset field returned as set!");
+    if (ooe.is_set_integer64())
+      throw new RuntimeException("isSet method error: unset field returned as set!");
+    if (ooe.is_set_some_characters())
+      throw new RuntimeException("isSet method error: unset field returned as set!");
+
+    for (int i = 1; i < 12; i++){
+      if (ooe.isSet(i))
+        throw new RuntimeException("isSet method error: unset field " + i + " returned as set!");
+    }
+
+    // Everything is set
+    ooe.set_a_bite((byte) 1);
+    ooe.set_base64("bytes".getBytes());
+    ooe.set_byte_list(new LinkedList());
+    ooe.set_double_precision(1);
+    ooe.set_i16_list(new LinkedList());
+    ooe.set_i64_list(new LinkedList());
+    ooe.set_boolean_field(true);
+    ooe.set_integer16((short) 1);
+    ooe.set_integer32(1);
+    ooe.set_integer64(1);
+    ooe.set_some_characters("string");
+
+    if (!ooe.is_set_a_bite())
+      throw new RuntimeException("isSet method error: set field returned as unset!");
+    if (!ooe.is_set_base64())
+      throw new RuntimeException("isSet method error: set field returned as unset!");
+    if (!ooe.is_set_byte_list())
+      throw new RuntimeException("isSet method error: set field returned as unset!");
+    if (!ooe.is_set_double_precision())
+      throw new RuntimeException("isSet method error: set field returned as unset!");
+    if (!ooe.is_set_i16_list())
+      throw new RuntimeException("isSet method error: set field returned as unset!");
+    if (!ooe.is_set_i64_list())
+      throw new RuntimeException("isSet method error: set field returned as unset!");
+    if (!ooe.is_set_boolean_field())
+      throw new RuntimeException("isSet method error: set field returned as unset!");
+    if (!ooe.is_set_integer16())
+      throw new RuntimeException("isSet method error: set field returned as unset!");
+    if (!ooe.is_set_integer32())
+      throw new RuntimeException("isSet method error: set field returned as unset!");
+    if (!ooe.is_set_integer64())
+      throw new RuntimeException("isSet method error: set field returned as unset!");
+    if (!ooe.is_set_some_characters())
+      throw new RuntimeException("isSet method error: set field returned as unset!");
+
+    for (int i = 1; i < 12; i++){
+      if (!ooe.isSet(i))
+        throw new RuntimeException("isSet method error: set field " + i + " returned as unset!");
+    }
+
+    // Should throw exception when field doesn't exist
+    boolean exceptionThrown = false;
+    try{
+      if (ooe.isSet(100));
+    } catch (IllegalArgumentException e){
+      exceptionThrown = true;
+    }
+    if (!exceptionThrown)
+      throw new RuntimeException("isSet method error: non-existent field provided as agument but no exception thrown!");
+  }
+}