Read Contacts information in Android system.

1. add user perimission

<uses-permission android:name="android.permission.READ_CONTACTS"/>

2. This is the data entity

import java.util.List;

public class Contact {
	// Phone number
	private List<String> mPhoneNumbers;

	public void setPhoneNumbers(List<String> phontNumberList) {
		this.mPhoneNumbers = phontNumberList;
	}

	public List<String> getPhoneNumbers() {
		return mPhoneNumbers;
	}
	
	// Display Name
	public void setDisplayName(String displayName) {
		this.mDisplayName = displayName;
	}

	public String getDisplayName() {
		return mDisplayName;
	}

	private String mDisplayName;

	//Contact ID
	private long mContactID;
	
	public void setContactID(long contactID) {
		mContactID = contactID;
	}

	public long getContactID() {
		return mContactID;
	}

	// Photo ID
	private long mPhotoID;
	
	public void setPhotoID(long photoID) {
		mPhotoID = photoID;
	}

	public long getPhotoID() {
		return mPhotoID;
	}
}

3. Create Contacts Manager

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

import android.content.ContentResolver;
import android.content.Context;
import android.database.Cursor;
import android.provider.ContactsContract;

public class ContactsManager {
	private static ContactsManager instance = null;
	
	private List<Contact> mContactList;
	
	private ContactsManager(Context context) {
		mContactList = GetAllContacts(context);
	}
	
	public static ContactsManager getInstance(Context context) {
		if(instance == null) {
			instance = new ContactsManager(context);
		}
		return instance;
	}
	
	private List<Contact> GetAllContacts(Context context)
	{
		List<Contact> contactList = new ArrayList<Contact>();
		ContentResolver resolver = context.getContentResolver();
		// 获取手机联系人
		Cursor phoneCursor = resolver.query(ContactsContract.Contacts.CONTENT_URI,null, null, null, null);
		if (phoneCursor != null) {
			while (phoneCursor.moveToNext()) {
				Contact c = new Contact();
				// set display name
				String displayName = phoneCursor.getString(
						phoneCursor.getColumnIndex(ContactsContract.Contacts.DISPLAY_NAME));
				c.setDisplayName(displayName);
				// set contactID
				String contactId = phoneCursor.getString(
						phoneCursor.getColumnIndex(ContactsContract.Contacts._ID));
				c.setContactID(Long.parseLong(contactId));
				// has phoneNumberFlag
				String hasPhone = phoneCursor.getString(
						phoneCursor.getColumnIndex(ContactsContract.Contacts.HAS_PHONE_NUMBER));
				// 如果有电话号码
				if (hasPhone.compareTo("1") == 0)
				{
					Cursor phones = resolver.query(ContactsContract.CommonDataKinds.Phone.CONTENT_URI,null
							,ContactsContract.CommonDataKinds.Phone.CONTACT_ID +" = "+ contactId,null, null);
					List<String> phoneNumbers = new ArrayList<String>();
					while (phones.moveToNext()) 
					{
						String phoneNumber = phones.getString(phones.getColumnIndex(ContactsContract.CommonDataKinds.Phone.NUMBER));
						phoneNumbers.add(phoneNumber);
					}
					c.setPhoneNumbers(phoneNumbers);
				}
				// set Photo ID
				String photoID = phoneCursor.getString(
						phoneCursor.getColumnIndex(ContactsContract.Contacts.PHOTO_ID));
				if(photoID != null)
					c.setPhotoID(Long.parseLong(photoID));
				else
					c.setPhotoID(0);				// add to list
				contactList.add(c);
			}
		}
		return contactList;
	}
	
	public List<Contact> getContactList()
	{
		return mContactList;
	}
	
	public String getContactName(long contactID)
	{
		String name="";
		if(mContactList != null)
		{
			for(int i=0; i<mContactList.size();i++)
			{
				Contact contact = mContactList.get(i);
				if(contact.getContactID() == contactID)
				{
					name = contact.getDisplayName();
					break;
				}
			}
		}
		return name;
	}
}

4. Usage

ContactsManager contactsManager = ContactsManager.getInstance(SMSService.this);

If you use it in Activity, just pass the Activity as context. I am using it in the service.