Android Cursor for JSONArray.

JSONArrayCursor.java

package com.s16.data;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

import android.database.AbstractCursor;
import android.os.Bundle;

public class JSONArrayCursor extends AbstractCursor {

	public static final String DATA_KEY = "d";
	
	private JSONArray mJsonArray;
	private String[] mColumnNames;
	private JSONObject mJsonObject;
	
	public JSONArrayCursor(JSONObject jsonObject) {
		if (jsonObject != null) {
			JSONObject tempObj = null;
			if(jsonObject.has(DATA_KEY)) {
				try {
					mJsonArray = jsonObject.getJSONArray(DATA_KEY);
				} catch (JSONException e) {
					e.printStackTrace();
				}
			}
			
			if (mJsonArray == null) {
				try {
					tempObj = jsonObject.getJSONObject(DATA_KEY);
				} catch (JSONException e) {
					e.printStackTrace();
				}
				if (tempObj != null) {
					mJsonArray = new JSONArray();
					mJsonArray.put(tempObj);
				}
			}
			
			initialize();	
		}
	}
	
	public JSONArrayCursor(JSONArray jsonArray) {
		mJsonArray = jsonArray;
		initialize();
	}
	
	private void initialize() {
		if (mJsonArray != null && mJsonArray.length() > 0) {
			JSONObject jsonObject = null;
			try {
				jsonObject = mJsonArray.getJSONObject(0);
			} catch (JSONException e) {
				e.printStackTrace();
			}
			if (jsonObject != null) {
				Iterator<String> keys = jsonObject.keys();
				if (keys != null) {
					List<String> list = new ArrayList<String>();
					while(keys.hasNext()) {
						String key = keys.next();
						list.add(key);
					}
					mColumnNames = new String[list.size()];
					mColumnNames = list.toArray(mColumnNames);
				}
			}
		}
	}
	
	@Override
	public int getCount() {
		if (mJsonArray != null) {
			return mJsonArray.length();
		}
		return 0;
	}

	@Override
	public String[] getColumnNames() {
		if (mColumnNames != null) {
			return mColumnNames;
		}
		return new String[] {};
	}

	@Override
	public String getString(int columnIndex) {
		if (mJsonObject != null) {
			String name = getColumnName(columnIndex);
			if (name != null) {
				try {
					return mJsonObject.getString(name);
				} catch (JSONException e) {
					e.printStackTrace();
				}
			}
		}
		return null;
	}

	@Override
	public short getShort(int columnIndex) {
		if (mJsonObject != null) {
			String name = getColumnName(columnIndex);
			if (name != null) {
				try {
					return (short)mJsonObject.getInt(name);
				} catch (JSONException e) {
					e.printStackTrace();
				}
			}
		}
		return 0;
	}

	@Override
	public int getInt(int columnIndex) {
		if (mJsonObject != null) {
			String name = getColumnName(columnIndex);
			if (name != null) {
				try {
					return mJsonObject.getInt(name);
				} catch (JSONException e) {
					e.printStackTrace();
				}
			}
		}
		return 0;
	}

	@Override
	public long getLong(int columnIndex) {
		if (mJsonObject != null) {
			String name = getColumnName(columnIndex);
			if (name != null) {
				try {
					return mJsonObject.getLong(name);
				} catch (JSONException e) {
					e.printStackTrace();
				}
			}
		}
		return 0;
	}

	@Override
	public float getFloat(int columnIndex) {
		if (mJsonObject != null) {
			String name = getColumnName(columnIndex);
			if (name != null) {
				try {
					return (float)mJsonObject.getDouble(name);
				} catch (JSONException e) {
					e.printStackTrace();
				}
			}
		}
		return 0;
	}

	@Override
	public double getDouble(int columnIndex) {
		if (mJsonObject != null) {
			String name = getColumnName(columnIndex);
			if (name != null) {
				try {
					return mJsonObject.getDouble(name);
				} catch (JSONException e) {
					e.printStackTrace();
				}
			}
		}
		return 0;
	}

	@Override
	public boolean isNull(int columnIndex) {
		if (mJsonObject != null) {
			String name = getColumnName(columnIndex);
			if (name != null) {
				return mJsonObject.isNull(name);
			}
		}
		return true;
	}

	@Override
	public boolean onMove(int oldPosition, int newPosition) {
		if (mJsonArray == null) return false;
		if (oldPosition != newPosition || mJsonObject == null) {
			
			try {
				mJsonObject = mJsonArray.getJSONObject(newPosition);
			} catch (JSONException e) {
				e.printStackTrace();
			}
			
			return true;
		}
        return false;
    }
	
	@Override
	public Bundle respond(Bundle extras) {
		Bundle result = new Bundle();
		result.putString(DATA_KEY, toJSONString());
		result.putInt("count", getCount());
		result.putStringArray("columns", mColumnNames);
		result.putInt("position", mPos);
		result.putString("current", (mJsonObject != null) ? mJsonObject.toString() : "");
		
		return result;
	}
	
	@Override
	public String toString() {
		if (mJsonArray != null) {
			return toJSONString();
		}
		return super.toString();
	}
	
	public String toJSONString() {
		if (mJsonArray != null) {
			JSONObject result = new JSONObject();
			try {
				result.put(DATA_KEY, mJsonArray);
			} catch (JSONException e) {
				e.printStackTrace();
			}
			return result.toString();
		}
		return "";
	}
}