下面列出了android.database.CursorWindow#releaseReference ( ) 实例代码，或者点击链接到github查看源代码，也可以在右侧发表评论。
@Override
public void fillWindow(int position, CursorWindow window) {
if (position < 0 || position > getCount()) {
return;
}
window.acquireReference();
try {
moveToPosition(position - 1);
window.clear();
window.setStartPosition(position);
int columnNum = getColumnCount();
window.setNumColumns(columnNum);
boolean isFull = false;
int numRows = 10;
while (!isFull && --numRows > 0 && moveToNext() && window.allocRow()) {
for (int i = 0; i < columnNum; i++) {
String field = getString(i);
if (field != null) {
if (!window.putString(field, getPosition(), i)) {
window.freeLastRow();
isFull = true;
break;
}
} else {
if (!window.putNull(getPosition(), i)) {
window.freeLastRow();
isFull = true;
break;
}
}
}
}
} catch (IllegalStateException e) {
// simply ignore it
} finally {
window.releaseReference();
}
}
/**
* Executes a statement and populates the specified {@link CursorWindow}
* with a range of results. Returns the number of rows that were counted
* during query execution.
*
* @param sql The SQL statement to execute.
* @param bindArgs The arguments to bind, or null if none.
* @param window The cursor window to clear and fill.
* @param startPos The start position for filling the window.
* @param requiredPos The position of a row that MUST be in the window.
* If it won't fit, then the query should discard part of what it filled
* so that it does. Must be greater than or equal to <code>startPos</code>.
* @param countAllRows True to count all rows that the query would return
* regagless of whether they fit in the window.
* @param cancellationSignal A signal to cancel the operation in progress, or null if none.
* @return The number of rows that were counted during query execution. Might
* not be all rows in the result set unless <code>countAllRows</code> is true.
*
* @throws SQLiteException if an error occurs, such as a syntax error
* or invalid number of bind arguments.
* @throws OperationCanceledException if the operation was canceled.
*/
public int executeForCursorWindow(String sql, Object[] bindArgs,
CursorWindow window, int startPos, int requiredPos, boolean countAllRows,
CancellationSignal cancellationSignal) {
if (sql == null) {
throw new IllegalArgumentException("sql must not be null.");
}
if (window == null) {
throw new IllegalArgumentException("window must not be null.");
}
window.acquireReference();
try {
int actualPos = -1;
int countedRows = -1;
int filledRows = -1;
final int cookie = mRecentOperations.beginOperation("executeForCursorWindow",
sql, bindArgs);
try {
final PreparedStatement statement = acquirePreparedStatement(sql);
try {
throwIfStatementForbidden(statement);
bindArguments(statement, bindArgs);
applyBlockGuardPolicy(statement);
attachCancellationSignal(cancellationSignal);
try {
final long result = nativeExecuteForCursorWindow(
mConnectionPtr, statement.mStatementPtr, window.mWindowPtr,
startPos, requiredPos, countAllRows);
actualPos = (int)(result >> 32);
countedRows = (int)result;
filledRows = window.getNumRows();
window.setStartPosition(actualPos);
return countedRows;
} finally {
detachCancellationSignal(cancellationSignal);
}
} finally {
releasePreparedStatement(statement);
}
} catch (RuntimeException ex) {
mRecentOperations.failOperation(cookie, ex);
throw ex;
} finally {
if (mRecentOperations.endOperationDeferLog(cookie)) {
mRecentOperations.logOperation(cookie, "window='" + window
+ "', startPos=" + startPos
+ ", actualPos=" + actualPos
+ ", filledRows=" + filledRows
+ ", countedRows=" + countedRows);
}
}
} finally {
window.releaseReference();
}
}
@Override
public void fillWindow(int position, CursorWindow window) {
if (position < 0 || position > getCount()) {
return;
}
window.acquireReference();
try {
int oldpos = getPosition();
moveToPosition(position - 1);
window.clear();
window.setStartPosition(position);
int columnNum = getColumnCount();
window.setNumColumns(columnNum);
while (moveToNext() && window.allocRow()) {
int pos = getPosition();
for (int i = 0; i < columnNum; i++) {
boolean hasRoom = true;
switch (getColumnType(i)) {
case Types.DOUBLE:
hasRoom = fillRow(window, Double.valueOf(getDouble(i)), pos, i);
break;
case Types.NUMERIC:
hasRoom = fillRow(window, Long.valueOf(getLong(i)), pos, i);
break;
case Types.BLOB:
hasRoom = fillRow(window, getBlob(i), pos, i);
break;
case Types.LONGVARCHAR:
hasRoom = fillRow(window, getString(i), pos, i);
break;
case Types.NULL:
hasRoom = fillRow(window, null, pos, i);
break;
default:
// Ignore an unknown type.
}
if (!hasRoom) {
break;
}
}
}
moveToPosition(oldpos);
} catch (IllegalStateException e) {
// simply ignore it
} finally {
window.releaseReference();
}
}
@Override
public void fillWindow(int position, CursorWindow window) {
if (position < 0 || position > getCount()) {
return;
}
window.acquireReference();
try {
int oldpos = getPosition();
moveToPosition(position - 1);
window.clear();
window.setStartPosition(position);
int columnNum = getColumnCount();
window.setNumColumns(columnNum);
while (moveToNext() && window.allocRow()) {
int pos = getPosition();
for (int i = 0; i < columnNum; i++) {
boolean hasRoom = true;
switch (getColumnType(i)) {
case Types.DOUBLE:
hasRoom = fillRow(window, Double.valueOf(getDouble(i)), pos, i);
break;
case Types.NUMERIC:
hasRoom = fillRow(window, Long.valueOf(getLong(i)), pos, i);
break;
case Types.BLOB:
hasRoom = fillRow(window, getBlob(i), pos, i);
break;
case Types.LONGVARCHAR:
hasRoom = fillRow(window, getString(i), pos, i);
break;
case Types.NULL:
hasRoom = fillRow(window, null, pos, i);
break;
default:
// Ignore an unknown type.
}
if (!hasRoom) {
break;
}
}
}
moveToPosition(oldpos);
} catch (IllegalStateException e) {
// simply ignore it
} finally {
window.releaseReference();
}
}
@Override
public void fillWindow(int position, CursorWindow window) {
if (position < 0 || position > getCount()) {
return;
}
window.acquireReference();
try {
int oldpos = getPosition();
moveToPosition(position - 1);
window.clear();
window.setStartPosition(position);
int columnNum = getColumnCount();
window.setNumColumns(columnNum);
while (moveToNext() && window.allocRow()) {
int pos = getPosition();
for (int i = 0; i < columnNum; i++) {
boolean hasRoom = true;
switch (getColumnType(i)) {
case Types.DOUBLE:
hasRoom = fillRow(window, Double.valueOf(getDouble(i)), pos, i);
break;
case Types.NUMERIC:
hasRoom = fillRow(window, Long.valueOf(getLong(i)), pos, i);
break;
case Types.BLOB:
hasRoom = fillRow(window, getBlob(i), pos, i);
break;
case Types.LONGVARCHAR:
hasRoom = fillRow(window, getString(i), pos, i);
break;
case Types.NULL:
hasRoom = fillRow(window, null, pos, i);
break;
default:
// Ignore an unknown type.
}
if (!hasRoom) {
break;
}
}
}
moveToPosition(oldpos);
} catch (IllegalStateException e) {
// simply ignore it
} finally {
window.releaseReference();
}
}
/**
* Executes a statement and populates the specified {@link CursorWindow}
* with a range of results. Returns the number of rows that were counted
* during query execution.
*
* @param sql The SQL statement to execute.
* @param bindArgs The arguments to bind, or null if none.
* @param window The cursor window to clear and fill.
* @param startPos The start position for filling the window.
* @param requiredPos The position of a row that MUST be in the window.
* If it won't fit, then the query should discard part of what it filled
* so that it does. Must be greater than or equal to <code>startPos</code>.
* @param countAllRows True to count all rows that the query would return
* regagless of whether they fit in the window.
* @param cancellationSignal A signal to cancel the operation in progress, or null if none.
* @return The number of rows that were counted during query execution. Might
* not be all rows in the result set unless <code>countAllRows</code> is true.
*
* @throws SQLiteException if an error occurs, such as a syntax error
* or invalid number of bind arguments.
* @throws OperationCanceledException if the operation was canceled.
*/
public int executeForCursorWindow(String sql, Object[] bindArgs,
CursorWindow window, int startPos, int requiredPos, boolean countAllRows,
CancellationSignal cancellationSignal) {
if (sql == null) {
throw new IllegalArgumentException("sql must not be null.");
}
if (window == null) {
throw new IllegalArgumentException("window must not be null.");
}
window.acquireReference();
try {
int actualPos = -1;
int countedRows = -1;
int filledRows = -1;
final int cookie = mRecentOperations.beginOperation("executeForCursorWindow",
sql, bindArgs);
try {
final PreparedStatement statement = acquirePreparedStatement(sql);
try {
throwIfStatementForbidden(statement);
bindArguments(statement, bindArgs);
applyBlockGuardPolicy(statement);
attachCancellationSignal(cancellationSignal);
try {
final long result = nativeExecuteForCursorWindow(
mConnectionPtr, statement.mStatementPtr, window,
startPos, requiredPos, countAllRows);
actualPos = (int)(result >> 32);
countedRows = (int)result;
filledRows = window.getNumRows();
window.setStartPosition(actualPos);
return countedRows;
} finally {
detachCancellationSignal(cancellationSignal);
}
} finally {
releasePreparedStatement(statement);
}
} catch (RuntimeException ex) {
mRecentOperations.failOperation(cookie, ex);
throw ex;
} finally {
if (mRecentOperations.endOperationDeferLog(cookie)) {
mRecentOperations.logOperation(cookie, "window='" + window
+ "', startPos=" + startPos
+ ", actualPos=" + actualPos
+ ", filledRows=" + filledRows
+ ", countedRows=" + countedRows);
}
}
} finally {
window.releaseReference();
}
}
@Override
public void fillWindow(int position, CursorWindow window) {
if (position < 0 || position > getCount()) {
return;
}
window.acquireReference();
try {
int oldpos = mPos;
mPos = position - 1;
window.clear();
window.setStartPosition(position);
int columnNum = getColumnCount();
window.setNumColumns(columnNum);
while (moveToNext() && window.allocRow()) {
for (int i = 0; i < columnNum; i++) {
boolean hasRoom = true;
switch (getColumnType(i)) {
case Types.DOUBLE:
hasRoom = fillRow(window, Double.valueOf(getDouble(i)), mPos, i);
break;
case Types.NUMERIC:
hasRoom = fillRow(window, Long.valueOf(getLong(i)), mPos, i);
break;
case Types.BLOB:
hasRoom = fillRow(window, getBlob(i), mPos, i);
break;
case Types.LONGVARCHAR:
hasRoom = fillRow(window, getString(i), mPos, i);
break;
case Types.NULL:
hasRoom = fillRow(window, null, mPos, i);
break;
}
if (!hasRoom) {
break;
}
}
}
mPos = oldpos;
} catch (IllegalStateException e) {
// simply ignore it
} finally {
window.releaseReference();
}
}
@Override
public void fillWindow(int position, CursorWindow window) {
if (position < 0 || position > getCount()) {
return;
}
window.acquireReference();
try {
int oldpos = mPos;
mPos = position - 1;
window.clear();
window.setStartPosition(position);
int columnNum = getColumnCount();
window.setNumColumns(columnNum);
while (moveToNext() && window.allocRow()) {
for (int i = 0; i < columnNum; i++) {
boolean hasRoom = true;
switch (getColumnType(i)) {
case Types.DOUBLE:
hasRoom = fillRow(window, Double.valueOf(getDouble(i)), mPos, i);
break;
case Types.NUMERIC:
hasRoom = fillRow(window, Long.valueOf(getLong(i)), mPos, i);
break;
case Types.BLOB:
hasRoom = fillRow(window, getBlob(i), mPos, i);
break;
case Types.LONGVARCHAR:
hasRoom = fillRow(window, getString(i), mPos, i);
break;
case Types.NULL:
hasRoom = fillRow(window, null, mPos, i);
break;
}
if (!hasRoom) {
break;
}
}
}
mPos = oldpos;
} catch (IllegalStateException e) {
// simply ignore it
} finally {
window.releaseReference();
}
}