func()

in bind/genjava.go [1456:1588]
127 lines of code
32 McCabe index (conditional complexity)

func (g *JavaGen) GenC() error {
	var pkgName, pkgPath string
	if g.Pkg != nil {
		pkgName = g.Pkg.Name()
		pkgPath = g.Pkg.Path()
	} else {
		pkgName = "universe"
	}
	g.Printf(cPreamble, g.gobindOpts(), pkgPath)
	g.Printf("#include %q\n", pkgName+".h")
	if g.Pkg != nil {
		for _, pkg := range g.Pkg.Imports() {
			if g.validPkg(pkg) {
				g.Printf("#include \"%s.h\"\n", pkg.Name())
			}
		}
	}
	g.Printf("\n")

	for _, iface := range g.interfaces {
		g.Printf("jclass proxy_class_%s_%s;\n", g.pkgPrefix, iface.obj.Name())
		g.Printf("jmethodID proxy_class_%s_%s_cons;\n", g.pkgPrefix, iface.obj.Name())
		for _, m := range iface.summary.callable {
			if !g.isSigSupported(m.Type()) {
				g.Printf("// skipped method %s.%s with unsupported parameter or return types\n\n", iface.obj.Name(), m.Name())
				continue
			}
			g.Printf("static jmethodID mid_%s_%s;\n", iface.obj.Name(), m.Name())
		}
	}
	for _, s := range g.structs {
		g.Printf("jclass proxy_class_%s_%s;\n", g.pkgPrefix, s.obj.Name())
		g.Printf("jmethodID proxy_class_%s_%s_cons;\n", g.pkgPrefix, s.obj.Name())
	}
	g.Printf("\n")
	g.Printf("JNIEXPORT void JNICALL\n")
	g.Printf("Java_%s_%s__1init(JNIEnv *env, jclass _unused) {\n", g.jniPkgName(), java.JNIMangle(g.className()))
	g.Indent()
	g.Printf("jclass clazz;\n")
	for _, s := range g.structs {
		if jinf, ok := g.jstructs[s.obj]; ok {
			// Leave the class and constructor NULL for Java classes with no
			// default constructor.
			if !jinf.genNoargCon {
				continue
			}
		}
		g.Printf("clazz = (*env)->FindClass(env, %q);\n", g.jniClassSigPrefix(s.obj.Pkg())+g.javaTypeName(s.obj.Name()))
		g.Printf("proxy_class_%s_%s = (*env)->NewGlobalRef(env, clazz);\n", g.pkgPrefix, s.obj.Name())
		g.Printf("proxy_class_%s_%s_cons = (*env)->GetMethodID(env, clazz, \"<init>\", \"(I)V\");\n", g.pkgPrefix, s.obj.Name())
	}
	for _, iface := range g.interfaces {
		pkg := iface.obj.Pkg()
		g.Printf("clazz = (*env)->FindClass(env, %q);\n", g.jniClassSigPrefix(pkg)+JavaClassName(pkg)+"$proxy"+iface.obj.Name())
		g.Printf("proxy_class_%s_%s = (*env)->NewGlobalRef(env, clazz);\n", g.pkgPrefix, iface.obj.Name())
		g.Printf("proxy_class_%s_%s_cons = (*env)->GetMethodID(env, clazz, \"<init>\", \"(I)V\");\n", g.pkgPrefix, iface.obj.Name())
		if isErrorType(iface.obj.Type()) {
			// As a special case, Java Exceptions are passed to Go pretending to implement the Go error interface.
			// To complete the illusion, use the Throwable.getMessage method for proxied calls to the error.Error method.
			g.Printf("clazz = (*env)->FindClass(env, \"java/lang/Throwable\");\n")
			g.Printf("mid_error_Error = (*env)->GetMethodID(env, clazz, \"getMessage\", \"()Ljava/lang/String;\");\n")
			continue
		}
		g.Printf("clazz = (*env)->FindClass(env, %q);\n", g.jniClassSigPrefix(pkg)+g.javaTypeName(iface.obj.Name()))
		for _, m := range iface.summary.callable {
			if !g.isSigSupported(m.Type()) {
				g.Printf("// skipped method %s.%s with unsupported parameter or return types\n\n", iface.obj.Name(), m.Name())
				continue
			}
			sig := m.Type().(*types.Signature)
			res := sig.Results()
			retSig := "V"
			if res.Len() > 0 {
				if t := res.At(0).Type(); !isErrorType(t) {
					retSig = g.jniSigType(t)
				}
			}
			var jniParams string
			params := sig.Params()
			for i := 0; i < params.Len(); i++ {
				jniParams += g.jniSigType(params.At(i).Type())
			}
			g.Printf("mid_%s_%s = (*env)->GetMethodID(env, clazz, %q, \"(%s)%s\");\n",
				iface.obj.Name(), m.Name(), javaNameReplacer(lowerFirst(m.Name())), jniParams, retSig)
		}
		g.Printf("\n")
	}
	g.Outdent()
	g.Printf("}\n\n")
	for _, f := range g.funcs {
		g.genJNIFunc(f, "", nil, false, false)
	}
	for _, s := range g.structs {
		sName := s.obj.Name()
		cons := g.constructors[s.obj]
		jinf := g.jstructs[s.obj]
		for _, f := range cons {
			g.genJNIConstructor(f, sName)
		}
		if len(cons) == 0 && (jinf == nil || jinf.genNoargCon) {
			g.Printf("JNIEXPORT jint JNICALL\n")
			g.Printf("Java_%s_%s_%s(JNIEnv *env, jclass clazz) {\n", g.jniPkgName(), java.JNIMangle(g.javaTypeName(sName)), java.JNIMangle("__New"))
			g.Indent()
			g.Printf("return new_%s_%s();\n", g.pkgPrefix, sName)
			g.Outdent()
			g.Printf("}\n\n")
		}

		for _, m := range exportedMethodSet(types.NewPointer(s.obj.Type())) {
			var jm *java.Func
			if jinf != nil {
				jm = jinf.lookupMethod(m, g.hasThis(s.obj.Name(), m))
			}
			g.genJNIFunc(m, sName, jm, false, jinf != nil)
		}
		for _, f := range exportedFields(s.t) {
			g.genJNIField(s.obj, f)
		}
	}
	for _, iface := range g.interfaces {
		for _, m := range iface.summary.callable {
			g.genJNIFunc(m, iface.obj.Name(), nil, true, false)
			g.genMethodInterfaceProxy(iface.obj.Name(), m)
		}
	}
	for _, v := range g.vars {
		g.genJNIVar(v)
	}
	if len(g.err) > 0 {
		return g.err
	}
	return nil
}