问用于创建同一类型的多个对象的设计模式

EN

public class QueryParser {
  CharacterIterator iterator;
  QueryBuilder queryBuilder;
  QueryConditionBuilder queryConditionBuilder;

  public Query parse(String text) {
    iterator = new StringCharacterIterator(text);
    queryBuilder = new QueryBuilder();
    while (hasNext()) {
      queryConditionBuilder = new QueryConditionBuilder();
      conditionSeparator();
      queryCondition();
      queryBuilder.withCondition(queryConditionBuilder.getQueryCondition()); 
    }
    return queryBuilder.getQuery();
  }

  public void conditionSeparator() {
     // if the next character is an &, then advance the iterator
  }

  public void parseQueryCondition() {
    key();
    operator();
    value();
  }

  public void parseKey() {
    // ... keep reading until the next character is not alphabetic
    queryConditionBuilder.withKey(key);
  }

  public void parseOperator() {
    // ... could be as simple as a one character check
    queryConditionBuilder.withOperator(operator);
  }

  public void parseValue() {
    // ... probably a number, so just read until the next character is not a digit or you reach the end of a string
    queryConditionBuilder.withValue(value);
  }

  public Character peek() {
     // delegate to character iterator
  }

  public Character next() {
     // delegate to character iterator
  }

  public boolean hasNext() {
     // delegate to character iterator
  }
}