Where is joy?

I have always struggled with the concept of joy. I used to have the habit of linking joy with subjective happiness.
However James states: "Count it all joy, my brothers, when you meet trials of various kinds, for you know that the testing of your faith produces steadfastness."
This leads me to believe that joy is more of an attitude, objective happiness, and consistency in the hope of our faith.
David mourned and worshiped God through many psalms. Psalm 54:4 "Surely God is my help; the Lord is the one who sustains me."
God must be our foundation, our rock, the one who our security, faith and trust lies in.
Paul tells us in Romans 8:31-39 that if God is for us no one can be against us. This does not mean that there will be no person or situation that is considered a trial or produces suffereing, but what he is saying is that God is our foundation and shows us our purpose in Him. Nothing can seperate us from His love or our purpose in Him.
Romans 8:28 "And we know that for those who love God all things work together for good, for those who are called according to his purpose."
This is why Paul can say to the Philippians (4:4-7) "Rejoice in the Lord always, I will say it again: Rejoice! Let your gentlenss be evident to all. The Lord is near. Do not be anxious about anything, but in everything, by prayer and petition, with thanksgiving, present your requests to God. And the peace of God, which transcends all understanding, will guard your hearts and your minds in Christ Jesus."
This should be our response. Not to hide our emotion or pretend there is no suffereing or sadness, but to embrace it with joy in the strength and purpose of God in our hearts, persevering through prayer in faith.