Java HashMap.clear方法代码示例

import java.util.HashMap; //导入方法依赖的package包/类
public static void main(String[] args) throws Exception {
    HashMap<Integer, Object> hm = makeMap();
    hm = (HashMap<Integer, Object>)hm.clone();
    hm.clear();
    // There should no longer be a strong reference to testObject
    // the WeakReference should be nulled out by GC. If not,
    // we will hang here until timed out by the test harness.
    Object[] chain = null;
    while (wr.get() != null) {
        try {
            Object[] allocate = new Object[1000000];
            allocate[0] = chain;
            chain = allocate;
        } catch (OutOfMemoryError oome) {
            chain = null;
        }
        System.gc();
        Thread.sleep(100);
    }
}
 

import java.util.HashMap; //导入方法依赖的package包/类
public static void main(String[] args) {

    //create HashMap object
    HashMap hMap = new HashMap();

    //add key value pairs to HashMap
    hMap.put("1", "One");
    hMap.put("2", "Two");
    hMap.put("3", "Three");

    /*
      To remove all values or clear HashMap use
      void clear method() of HashMap class. Clear method removes all
      key value pairs contained in HashMap.
    */

    hMap.clear();

    System.out.println("Total key value pairs in HashMap are : " + hMap.size());
  }
 

import java.util.HashMap; //导入方法依赖的package包/类
/**
 * Tests the attribute in a scan node to limit the columns read by a scan.
 *
 * The functionality of selecting all columns is tested in all of the other tests that leave out the attribute.
 * @throws Exception
 */
@Test
public void testSelectColumnRead() throws Exception {
  HashMap<String, FieldInfo> fields = new HashMap<>();
  ParquetTestProperties props = new ParquetTestProperties(4, 3000, DEFAULT_BYTES_PER_PAGE, fields);
  // generate metatdata for a series of test columns, these columns are all generated in the test file
  populateFieldInfoMap(props);
  TestFileGenerator.generateParquetFile("/tmp/test.parquet", props);
  fields.clear();
  // create a new object to describe the dataset expected out of the scan operation
  // the fields added below match those requested in the plan specified in parquet_selective_column_read.json
  // that is used below in the test query
  props = new ParquetTestProperties(4, 3000, DEFAULT_BYTES_PER_PAGE, fields);
  props.fields.put("integer", new FieldInfo("int32", "integer", 32, TestFileGenerator.intVals, TypeProtos.MinorType.INT, props));
  props.fields.put("bigInt", new FieldInfo("int64", "bigInt", 64, TestFileGenerator.longVals, TypeProtos.MinorType.BIGINT, props));
  props.fields.put("bin", new FieldInfo("binary", "bin", -1, TestFileGenerator.binVals, TypeProtos.MinorType.VARBINARY, props));
  props.fields.put("bin2", new FieldInfo("binary", "bin2", -1, TestFileGenerator.bin2Vals, TypeProtos.MinorType.VARBINARY, props));
  testParquetFullEngineEventBased(true, false, "/parquet/parquet_selective_column_read.json", null, "/tmp/test.parquet", 1, props, QueryType.PHYSICAL);
}
 

import java.util.HashMap; //导入方法依赖的package包/类
/**
 * init the cache on your own.
 *
 * @param recyclerView
 * @param items
 */
public void apply(RecyclerView recyclerView, Iterable<Item> items) {
    if (items != null) {
        //we pre-create the views for our cache
        HashMap<Integer, Stack<RecyclerView.ViewHolder>> cache = new HashMap<>();
        for (Item d : items) {
            if (!cache.containsKey(d.getType())) {
                cache.put(d.getType(), new Stack<RecyclerView.ViewHolder>());
            }

            if (mCacheSize == -1 || cache.get(d.getType()).size() <= mCacheSize) {
                cache.get(d.getType()).push(d.getViewHolder(recyclerView));
            }

            RecyclerView.RecycledViewPool recyclerViewPool = new RecyclerView.RecycledViewPool();

            //we fill the pool
            for (Map.Entry<Integer, Stack<RecyclerView.ViewHolder>> entry : cache.entrySet()) {
                recyclerViewPool.setMaxRecycledViews(entry.getKey(), mCacheSize);

                for (RecyclerView.ViewHolder holder : entry.getValue()) {
                    recyclerViewPool.putRecycledView(holder);
                }

                //make sure to clear the stack
                entry.getValue().clear();
            }

            //make sure to clear the cache
            cache.clear();

            recyclerView.setRecycledViewPool(recyclerViewPool);
        }
    }
}
 

import java.util.HashMap; //导入方法依赖的package包/类
public void testMSSQL2005() throws Exception {
    /*
            add(getMessage("DRIVERNAME_MSSQL2005"),
    "com.microsoft.sqlserver.jdbc.SQLServerDriver",
    "jdbc:sqlserver://[<HOST>[\\<INSTANCE>][:<PORT>]][;databaseName=<DB>][;<ADDITIONAL>]", true);
    */
    ArrayList<String> supportedProps = new ArrayList<String>();
    supportedProps.addAll(STD_SUPPORTED_PROPS);
    supportedProps.add(JdbcUrl.TOKEN_INSTANCE);
    
    ArrayList<String> requiredProps = new ArrayList<String>();
    JdbcUrl url = checkUrl(getDriverName("DRIVERNAME_MSSQL2005"), null, 
            "com.microsoft.sqlserver.jdbc.SQLServerDriver", 
            "jdbc:sqlserver://[<HOST>[\\<INSTANCE>][:<PORT>]][;databaseName=<DB>][;<ADDITIONAL>]", 
            supportedProps, requiredProps);
    
    HashMap<String, String> propValues = buildPropValues(supportedProps);        
    testUrlString(url, propValues, "jdbc:sqlserver://" + HOST + "\\" + INSTANCE + ":" + PORT + ";databaseName=" + DB + ";" + ADDITIONAL);

    propValues.remove(JdbcUrl.TOKEN_ADDITIONAL);
    testUrlString(url, propValues, "jdbc:sqlserver://" + HOST + "\\" + INSTANCE + ":" + PORT + ";databaseName=" + DB);
    
    propValues.remove(JdbcUrl.TOKEN_PORT);
    testUrlString(url, propValues, "jdbc:sqlserver://" + HOST + "\\" + INSTANCE + ";databaseName=" + DB);
    
    propValues.remove(JdbcUrl.TOKEN_INSTANCE);
    testUrlString(url, propValues, "jdbc:sqlserver://" + HOST + ";databaseName=" + DB);
    
    propValues.remove(JdbcUrl.TOKEN_DB);
    testUrlString(url, propValues, "jdbc:sqlserver://" + HOST);
    
    propValues.remove(JdbcUrl.TOKEN_HOST);
    propValues.put(JdbcUrl.TOKEN_DB, DB);
    testUrlString(url, propValues, "jdbc:sqlserver://;databaseName=" + DB);
    
    propValues.clear();
    testUrlString(url, propValues, "jdbc:sqlserver://");
    
}
 

import java.util.HashMap; //导入方法依赖的package包/类
private void updateFile(HashMap<File, ArrayList<String>> file_data_temp, boolean reload) {
    file_data_temp.clear();
    if(file != null) {
        if(!file.exists()) {
            file_data_temp.put(file, null);
        } else {
            if(file.isFile()) {
                ArrayList<String> data = new ArrayList<>();/*
                if(file.exists()) {
                    try (Scanner scanner = new Scanner(file)) {
                        while(scanner.hasNextLine()) {
                            String line = scanner.nextLine();
                            data.add(line);
                        }
                        scanner.close();
                    } catch (Exception ex) {
                        StaticStandard.logErr("Error while scanning file: " + ex);
                    }
                }*/
                file_data_temp.put(file, data);
            } else if(file.isDirectory()) {
                addFolder(file, file_data_temp);
            }
        }
    }
    if(reload) {
        reloadFile();
    }
}
 

import java.util.HashMap; //导入方法依赖的package包/类
@Override
public View getView(int position, View convertView, ViewGroup parent) {
    SimpleMonthView v;
    HashMap<String, Integer> drawingParams = null;
    if (convertView != null) {
        v = (SimpleMonthView) convertView;
        drawingParams = (HashMap<String, Integer>) v.getTag();
    } else {
        v = new SimpleMonthView(mContext);
        v.setLayoutParams(new AbsListView.LayoutParams(
                LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT));
        v.setClickable(true);
        v.setOnDayClickListener(this);
    }
    if (drawingParams == null) {
        drawingParams = new HashMap<String, Integer>();
    }
    drawingParams.clear();

    final int month = position % MONTHS_IN_YEAR;
    final int year = position / MONTHS_IN_YEAR + mController.getMinYear();

    int selectedDay = -1;
    if (isSelectedDayInMonth(year, month)) {
        selectedDay = mSelectedDay.day;
    }

    v.reuse();

    drawingParams
            .put(SimpleMonthView.VIEW_PARAMS_SELECTED_DAY, selectedDay);
    drawingParams.put(SimpleMonthView.VIEW_PARAMS_YEAR, year);
    drawingParams.put(SimpleMonthView.VIEW_PARAMS_MONTH, month);
    drawingParams.put(SimpleMonthView.VIEW_PARAMS_WEEK_START,
            mController.getFirstDayOfWeek());
    v.setMonthParams(drawingParams);
    v.invalidate();

    return v;
}
 

import java.util.HashMap; //导入方法依赖的package包/类
public void invalidateCurrentSession(HttpServletRequest request) {
        /*
        FIXME
        if (!octopusConfig.getIsSessionInvalidatedAtLogin()) {
            // Defined with config that developer don't was logout/session invalidation.
            return;
        }
*/

        /*
        if (SecurityUtils.getSubject() instanceof TwoStepSubject) {
            // Otherwise the principals are cleared from the current subject which isn't something we want :)
            return;
        }
        */
        HttpSession session = request.getSession();

        HashMap<String, Object> content = new HashMap<>();
        Enumeration keys = session.getAttributeNames();

        while (keys.hasMoreElements()) {
            String key = (String) keys.nextElement();
            content.put(key, session.getAttribute(key));
            session.removeAttribute(key);
        }

        SecurityUtils.getSubject().logout();

        session = request.getSession(true);
        for (Map.Entry m : content.entrySet()) {
            session.setAttribute((String) m.getKey(), m.getValue());
        }
        content.clear();
    }
 

import java.util.HashMap; //导入方法依赖的package包/类
private void put(K key, V value){

            if (queue.get(queue.size() - 1).size() >= bufferSize) {
                if (queue.size() < queueLen) {
                    queue.add(new HashMap<>());
                } else {
                    HashMap<K, V> remove = queue.remove(0);
                    remove.clear();
                    queue.add(remove);
                }
            }

            queue.get(queue.size() - 1).put(key, value);
        }
 

import java.util.HashMap; //导入方法依赖的package包/类
public Node(ArrayList<double[]> data)
{
    this.dataList = data;
    leftNode = null;
    rightNode = null;
    isLeaf = true;
    //Calculate Gini-impurity
    HashMap<Double, Integer>classType = new HashMap();
    for(double[] dataValue : dataList)
    {
        if(!classType.containsKey(dataValue[dataValue.length - 1]))
            classType.put(dataValue[dataValue.length - 1], 1);
        else
        {
            int count = classType.get(dataValue[dataValue.length - 1]) + 1;
            classType.put(dataValue[dataValue.length - 1], count);
        }
    }
    impurity = 1;
    double count, dataSize = dataList.size();
    double maxCount = -1;
    for(double classIndex : classType.keySet())
    {
        count = classType.get(classIndex);
        impurity = impurity - Math.pow(count/dataSize, 2);
        if(count > maxCount)
        {
            majorityType = classIndex;
            maxCount = count;
        }
    }
    classType.clear();
}
 

import java.util.HashMap; //导入方法依赖的package包/类
public HashMap<String, Object> updateContext(HashMap<String, Object> newContext) {
    if (odooSession != null && odooSession.userContext() != null)
        newContext.putAll(odooSession.userContext());
    if (user != null) {
        newContext.clear();
        newContext.put("uid", user.getUserId());
        newContext.put("tz", user.getTimezone());
    }
    return newContext;
}
 

import java.util.HashMap; //导入方法依赖的package包/类
/**
 * Fetches entries from local and remote nodes and appends these to register-interest response.
 */
public void fetchEntries(HashMap<Integer, HashSet> bucketKeys, VersionedObjectList values,
    ServerConnection servConn) throws IOException {
  int retryAttempts = calcRetry();
  RetryTimeKeeper retryTime = null;
  HashMap<Integer, HashSet> failures = new HashMap<Integer, HashSet>(bucketKeys);
  HashMap<InternalDistributedMember, HashMap<Integer, HashSet>> nodeToBuckets =
      new HashMap<InternalDistributedMember, HashMap<Integer, HashSet>>();

  while (--retryAttempts >= 0 && !failures.isEmpty()) {
    nodeToBuckets.clear();
    updateNodeToBucketMap(nodeToBuckets, failures);
    failures.clear();

    HashMap<Integer, HashSet> localBuckets = nodeToBuckets.remove(getMyId());
    if (localBuckets != null && !localBuckets.isEmpty()) {
      Set keys = new HashSet();
      for (Integer id : localBuckets.keySet()) {
        keys.addAll(localBuckets.get(id));
      }
      if (!keys.isEmpty()) {
        BaseCommand.appendNewRegisterInterestResponseChunkFromLocal(this, values, "keyList", keys,
            servConn);
      }
    }

    // Handle old nodes for Rolling Upgrade support
    Set<Integer> failedSet = handleOldNodes(nodeToBuckets, values, servConn);
    // Add failed buckets to nodeToBuckets map so that these will be tried on
    // remote nodes.
    if (!failedSet.isEmpty()) {
      for (Integer bId : failedSet) {
        failures.put(bId, bucketKeys.get(bId));
      }
      updateNodeToBucketMap(nodeToBuckets, failures);
      failures.clear();
    }

    fetchRemoteEntries(nodeToBuckets, failures, values, servConn);
    if (!failures.isEmpty()) {
      if (retryTime == null) {
        retryTime = new RetryTimeKeeper(this.retryTimeout);
      }
      if (!waitForFetchRemoteEntriesRetry(retryTime)) {
        break;
      }
    }
  }
  if (!failures.isEmpty()) {
    throw new InternalGemFireException("Failed to fetch entries from " + failures.size()
        + " buckets of region " + getName() + " for register interest.");
  }
}
 

import java.util.HashMap; //导入方法依赖的package包/类
private ECRFFieldValuesOutVO getEcrfFieldValues(ECRF ecrf, String section, ProbandListEntryOutVO listEntryVO, boolean addSeries, boolean jsValues, boolean loadAllJsValues,
		PSFVO psf) throws Exception {
	ECRFFieldValuesOutVO result = new ECRFFieldValuesOutVO();
	if (listEntryVO != null && ecrf != null) {
		ECRFFieldDao ecrfFieldDao = this.getECRFFieldDao();
		ECRFFieldValueDao ecrfFieldValueDao = this.getECRFFieldValueDao();
		Collection<Map> ecrfFieldValues = ecrfFieldValueDao.findByListEntryEcrfSectionJs(listEntryVO.getId(), ecrf.getId(), section, true, null, psf);
		HashMap<String, Long> maxSeriesIndexMap = null;
		HashMap<String, Long> fieldMaxPositionMap = null;
		HashMap<String, Long> fieldMinPositionMap = null;
		HashMap<String, Set<ECRFField>> seriesEcrfFieldMap = null;
		// HashMap<String, Set<ECRFField>> seriesEcrfFieldJsMap = null;
		if (addSeries) {
			maxSeriesIndexMap = new HashMap<String, Long>();
			fieldMaxPositionMap = new HashMap<String, Long>();
			fieldMinPositionMap = new HashMap<String, Long>();
			seriesEcrfFieldMap = new HashMap<String, Set<ECRFField>>();
			// seriesEcrfFieldJsMap = new HashMap<String, Set<ECRFField>>();
			ServiceUtil.initSeriesEcrfFieldMaps(
					ecrfFieldDao.findByTrialEcrfSectionSeriesJs(null, ecrf.getId(), section, true, true, null, null),
					listEntryVO.getId(),
					ecrf.getId(),
					maxSeriesIndexMap,
					fieldMaxPositionMap,
					fieldMinPositionMap,
					seriesEcrfFieldMap,
					// seriesEcrfFieldJsMap,
					ecrfFieldValueDao
					);
		}
		result.setPageValues(ServiceUtil.getEcrfFieldValues(listEntryVO, ecrfFieldValues, maxSeriesIndexMap, fieldMaxPositionMap, fieldMinPositionMap, seriesEcrfFieldMap,
				null,
				ecrfFieldDao,
				ecrfFieldValueDao,
				this.getECRFFieldStatusEntryDao(),
				this.getECRFFieldStatusTypeDao())); // this.getInputFieldSelectionSetValueDao()
		if (jsValues) {
			if (addSeries) {
				maxSeriesIndexMap.clear();
				fieldMaxPositionMap.clear();
				fieldMinPositionMap.clear();
				seriesEcrfFieldMap.clear();
				// seriesEcrfFieldJsMap.clear();
				ServiceUtil.initSeriesEcrfFieldMaps(
						(loadAllJsValues ? ecrfFieldDao.findByTrialEcrfSeriesJs(null, ecrf.getId(), true, true, true, null) :
							ecrfFieldDao.findByTrialEcrfSectionSeriesJs(null, ecrf.getId(), section, true, true, true, null)),
							listEntryVO.getId(),
							ecrf.getId(),
							maxSeriesIndexMap,
							fieldMaxPositionMap,
							fieldMinPositionMap,
							seriesEcrfFieldMap,
							// seriesEcrfFieldJsMap,
							ecrfFieldValueDao
						);
			}
			if (loadAllJsValues) {
				result.setJsValues(ServiceUtil.getEcrfFieldJsonValues(
						// ecrfFieldValueDao.findByListEntryEcrfSectionJs(listEntryVO.getId(), ecrf.getId(), section, true, true, null),
						ecrfFieldValueDao.findByListEntryEcrfJs(listEntryVO.getId(), ecrf.getId(), true, true, null),
						maxSeriesIndexMap, fieldMaxPositionMap,
						fieldMinPositionMap, seriesEcrfFieldMap,
						false, ecrfFieldValueDao,
						this.getInputFieldSelectionSetValueDao()));
			} else {
				result.setJsValues(ServiceUtil.getEcrfFieldJsonValues(ecrfFieldValues,
						maxSeriesIndexMap, fieldMaxPositionMap,
						fieldMinPositionMap, seriesEcrfFieldMap,
						true, ecrfFieldValueDao,
						this.getInputFieldSelectionSetValueDao()));
			}
		}
	}
	return result;
}
 

import java.util.HashMap; //导入方法依赖的package包/类
public void parseMultipartUpload()
              throws IOException {
  // setup the initial buffered input stream, boundary string that separates
  // various parts in the stream.
  startMultipartParse();

  HashMap partHeaders = parsePartHeaders();
  while (partHeaders != null) {

      String fieldName = (String)partHeaders.get("fieldName");
      String fileName = (String)partHeaders.get("fileName");

      if (fileName != null) {
          // This is a file upload part
          if (fileName.equals("")) {
              fileName = null; // empty filename, probably an "empty" file param
          }

          if (fileName != null) {
              // a filename was actually specified
              String content = (String)partHeaders.get("content-type");
              fileName = saveUploadFile(fileName, content);

              uploadFiles.put(fieldName, 
                  new OneUpload( 
                     uploadDir.toString(), 
                     fileName, 
                     content
                 )
              );
          }
          else {
              uploadFiles.put(fieldName, new OneUpload(null, null, null));
          }
      }
      else {
          // this is a parameters list part
          byte[] valueBytes = parseFormFieldBytes();
          String value = new String(valueBytes, fieldEncoding);

          Vector<String> existingValues = formFields.get(fieldName);
          if (existingValues == null) {
              existingValues = new Vector<String>();
              formFields.put(fieldName, existingValues);
          }
          existingValues.addElement(value);
      }

      partHeaders.clear();
      partHeaders = parsePartHeaders();
  }
}
 

import java.util.HashMap; //导入方法依赖的package包/类
@SuppressLint("NewApi")
@SuppressWarnings("unchecked")
@Override
public View getView(int position, View convertView, ViewGroup parent) {
    MonthView v;
    HashMap<String, Integer> drawingParams = null;
    if (convertView != null) {
        v = (MonthView) convertView;
        // We store the drawing parameters in the view so it can be recycled
        drawingParams = (HashMap<String, Integer>) v.getTag();
    } else {
        v = createMonthView(mContext);
        // Set up the new view
        LayoutParams params = new LayoutParams(
                LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT);
        v.setLayoutParams(params);
        v.setClickable(true);
        v.setOnDayClickListener(this);
    }
    if (drawingParams == null) {
        drawingParams = new HashMap<>();
    }
    drawingParams.clear();

    final int month = (position + mController.getStartDate().get(Calendar.MONTH)) % MONTHS_IN_YEAR;
    final int year = (position + mController.getStartDate().get(Calendar.MONTH)) / MONTHS_IN_YEAR + mController.getMinYear();

    int selectedDay = -1;
    if (isSelectedDayInMonth(year, month)) {
        selectedDay = mSelectedDay.day;
    }

    // Invokes requestLayout() to ensure that the recycled view is set with the appropriate
    // height/number of weeks before being displayed.
    v.reuse();

    drawingParams.put(MonthView.VIEW_PARAMS_SELECTED_DAY, selectedDay);
    drawingParams.put(MonthView.VIEW_PARAMS_YEAR, year);
    drawingParams.put(MonthView.VIEW_PARAMS_MONTH, month);
    drawingParams.put(MonthView.VIEW_PARAMS_WEEK_START, mController.getFirstDayOfWeek());
    v.setMonthParams(drawingParams);
    v.invalidate();
    return v;
}