Merge pull request #214 from markuspfeiffer/dev-where

Add support for count/exists queries.
pardom-zz · Apr 18, 2014 · 06d0c5d · 06d0c5d
2 parents 7b2ed13 + 1c8e7d3
commit 06d0c5d
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Showing 6 changed files with 606 additions and 75 deletions.
diff --git a/src/com/activeandroid/query/From.java b/src/com/activeandroid/query/From.java
@@ -34,7 +34,7 @@ public final class From implements Sqlable {
 	private Class<? extends Model> mType;
 	private String mAlias;
 	private List<Join> mJoins;
-	private String mWhere;
+	private final StringBuilder mWhere = new StringBuilder();
 	private String mGroupBy;
 	private String mHaving;
 	private String mOrderBy;
@@ -87,29 +87,41 @@ public Join crossJoin(Class<? extends Model> table) {
 		return join;
 	}
 
-    public From where(String where) {
-        if (mWhere != null) {                                   // Chain conditions if a previous
-            mWhere = mWhere + " AND " + where;                  // condition exists.
-        } else {
-            mWhere = where;
+    public From where(String clause) {
+        // Chain conditions if a previous condition exists.
+        if (mWhere.length() > 0) {
+            mWhere.append(" AND ");
         }
+        mWhere.append(clause);
+        return this;
+    }
 
+    public From where(String clause, Object... args) {
+        where(clause).addArguments(args);
         return this;
     }
 
-    public From where(String where, Object... args) {
-        if (mWhere != null) {                                    // Chain conditions if a previous
-            mWhere = mWhere + " AND " + where;                   // condition exists.
-        }
-        else {
-            mWhere = where;
-        }
+    public From and(String clause) {
+        return where(clause);
+    }
 
-        addArguments(args);
+    public From and(String clause, Object... args) {
+        return where(clause, args);
+    }
 
+    public From or(String clause) {
+        if (mWhere.length() > 0) {
+            mWhere.append(" OR ");
+        }
+        mWhere.append(clause);
         return this;
     }
 
+    public From or(String clause, Object... args) {
+        or(clause).addArguments(args);
+        return this;
+    }
+
 	public From groupBy(String groupBy) {
 		mGroupBy = groupBy;
 		return this;
@@ -144,99 +156,182 @@ public From offset(String offset) {
 	}
 
 	void addArguments(Object[] args) {
-        for( Object arg : args ) {
-            if (arg.getClass() == boolean.class || arg.getClass() == Boolean.class)
-                arg = ( arg.equals(true) ? 1 : 0 );
-
+        for(Object arg : args) {
+            if (arg.getClass() == boolean.class || arg.getClass() == Boolean.class) {
+                arg = (arg.equals(true) ? 1 : 0);
+            }
             mArguments.add(arg);
         }
 	}
 
-	@Override
-	public String toSql() {
-		StringBuilder sql = new StringBuilder();
-		sql.append(mQueryBase.toSql());
-		sql.append("FROM ");
-		sql.append(Cache.getTableName(mType)).append(" ");
+    private void addFrom(final StringBuilder sql) {
+        sql.append("FROM ");
+        sql.append(Cache.getTableName(mType)).append(" ");
 
-		if (mAlias != null) {
-			sql.append("AS ");
-			sql.append(mAlias);
-			sql.append(" ");
-		}
+        if (mAlias != null) {
+            sql.append("AS ");
+            sql.append(mAlias);
+            sql.append(" ");
+        }
+    }
 
-		for (Join join : mJoins) {
-			sql.append(join.toSql());
-		}
+    private void addJoins(final StringBuilder sql) {
+        for (final Join join : mJoins) {
+            sql.append(join.toSql());
+        }
+    }
 
-		if (mWhere != null) {
-			sql.append("WHERE ");
-			sql.append(mWhere);
-			sql.append(" ");
-		}
+    private void addWhere(final StringBuilder sql) {
+        if (mWhere.length() > 0) {
+            sql.append("WHERE ");
+            sql.append(mWhere);
+            sql.append(" ");
+        }
+    }
 
-		if (mGroupBy != null) {
-			sql.append("GROUP BY ");
-			sql.append(mGroupBy);
-			sql.append(" ");
-		}
+    private void addGroupBy(final StringBuilder sql) {
+        if (mGroupBy != null) {
+            sql.append("GROUP BY ");
+            sql.append(mGroupBy);
+            sql.append(" ");
+        }
+    }
 
-		if (mHaving != null) {
-			sql.append("HAVING ");
-			sql.append(mHaving);
-			sql.append(" ");
-		}
+    private void addHaving(final StringBuilder sql) {
+        if (mHaving != null) {
+            sql.append("HAVING ");
+            sql.append(mHaving);
+            sql.append(" ");
+        }
+    }
 
-		if (mOrderBy != null) {
-			sql.append("ORDER BY ");
-			sql.append(mOrderBy);
-			sql.append(" ");
-		}
+    private void addOrderBy(final StringBuilder sql) {
+        if (mOrderBy != null) {
+            sql.append("ORDER BY ");
+            sql.append(mOrderBy);
+            sql.append(" ");
+        }
+    }
 
-		if (mLimit != null) {
-			sql.append("LIMIT ");
-			sql.append(mLimit);
-			sql.append(" ");
-		}
+    private void addLimit(final StringBuilder sql) {
+        if (mLimit != null) {
+            sql.append("LIMIT ");
+            sql.append(mLimit);
+            sql.append(" ");
+        }
+    }
 
-		if (mOffset != null) {
-			sql.append("OFFSET ");
-			sql.append(mOffset);
-			sql.append(" ");
-		}
+    private void addOffset(final StringBuilder sql) {
+        if (mOffset != null) {
+            sql.append("OFFSET ");
+            sql.append(mOffset);
+            sql.append(" ");
+        }
+    }
 
-		// Don't wast time building the string
-		// unless we're going to log it.
-		if (Log.isEnabled()) {
-			Log.v(sql.toString() + " " + TextUtils.join(",", getArguments()));
-		}
+    private String sqlString(final StringBuilder sql) {
 
-		return sql.toString().trim();
-	}
+        final String sqlString = sql.toString().trim();
+
+        // Don't waste time building the string
+        // unless we're going to log it.
+        if (Log.isEnabled()) {
+            Log.v(sqlString + " " + TextUtils.join(",", getArguments()));
+        }
+
+        return sqlString;
+    }
+
+    @Override
+    public String toSql() {
+        final StringBuilder sql = new StringBuilder();
+        sql.append(mQueryBase.toSql());
+
+        addFrom(sql);
+        addJoins(sql);
+        addWhere(sql);
+        addGroupBy(sql);
+        addHaving(sql);
+        addOrderBy(sql);
+        addLimit(sql);
+        addOffset(sql);
+
+        return sqlString(sql);
+    }
+
+    public String toExistsSql() {
+
+        final StringBuilder sql = new StringBuilder();
+        sql.append("SELECT EXISTS(SELECT 1 ");
+
+        addFrom(sql);
+        addJoins(sql);
+        addWhere(sql);
+        addGroupBy(sql);
+        addHaving(sql);
+        addLimit(sql);
+        addOffset(sql);
+
+        sql.append(")");
+
+        return sqlString(sql);
+    }
+
+    public String toCountSql() {
+
+        final StringBuilder sql = new StringBuilder();
+        sql.append("SELECT COUNT(*) ");
+
+        addFrom(sql);
+        addJoins(sql);
+        addWhere(sql);
+        addGroupBy(sql);
+        addHaving(sql);
+        addLimit(sql);
+        addOffset(sql);
+
+        return sqlString(sql);
+    }
 
 	public <T extends Model> List<T> execute() {
 		if (mQueryBase instanceof Select) {
 			return SQLiteUtils.rawQuery(mType, toSql(), getArguments());
-		}
-		else {
+			
+		} else {
 			SQLiteUtils.execSql(toSql(), getArguments());
-			Cache.getContext().getContentResolver().notifyChange(ContentProvider
-					.createUri(mType, null), null);
+			Cache.getContext().getContentResolver().notifyChange(ContentProvider.createUri(mType, null), null);
 			return null;
+
 		}
 	}
 
 	public <T extends Model> T executeSingle() {
 		if (mQueryBase instanceof Select) {
 			limit(1);
 			return (T) SQLiteUtils.rawQuerySingle(mType, toSql(), getArguments());
-		}
-		else {
+			
+		} else {
 			limit(1);
 			SQLiteUtils.rawQuerySingle(mType, toSql(), getArguments()).delete();
 			return null;
+
 		}
 	}
+
+    /**
+     * Gets a value indicating whether the query returns any rows.
+     * @return <code>true</code> if the query returns at least one row; otherwise, <code>false</code>.
+     */
+    public boolean exists() {
+        return SQLiteUtils.intQuery(toExistsSql(), getArguments()) != 0;
+    }
+
+    /**
+     * Gets the number of rows returned by the query.
+     */
+    public int count() {
+        return SQLiteUtils.intQuery(toCountSql(), getArguments());
+    }
 
 	public String[] getArguments() {
 		final int size = mArguments.size();

diff --git a/src/com/activeandroid/util/SQLiteUtils.java b/src/com/activeandroid/util/SQLiteUtils.java
@@ -106,6 +106,14 @@ public static <T extends Model> List<T> rawQuery(Class<? extends Model> type, St
 
 		return entities;
 	}
+
+	public static int intQuery(final String sql, final String[] selectionArgs) {
+        final Cursor cursor = Cache.openDatabase().rawQuery(sql, selectionArgs);
+        final int number = processIntCursor(cursor);
+        cursor.close();
+
+        return number;
+	}
 
 	public static <T extends Model> T rawQuerySingle(Class<? extends Model> type, String sql, String[] selectionArgs) {
 		List<T> entities = rawQuery(type, sql, selectionArgs);
@@ -349,6 +357,13 @@ public static <T extends Model> List<T> processCursor(Class<? extends Model> typ
 		return entities;
 	}
 
+	private static int processIntCursor(final Cursor cursor) {
+        if (cursor.moveToFirst()) {
+            return cursor.getInt(0);
+	    }
+        return 0;
+    }
+
 	public static List<String> lexSqlScript(String sqlScript) {
 		ArrayList<String> sl = new ArrayList<String>();
 		boolean inString = false, quoteNext = false;