field.java

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            this.databaseName = getStringFromBytes(this.databaseNameStart,
                    this.databaseNameLength);
        }

        return this.databaseName;
    }

    /**
     * DOCUMENT ME!
     *
     * @return DOCUMENT ME!
     */
    public String getFullName() {
        if (this.fullName == null) {
            StringBuffer fullNameBuf = new StringBuffer(getTableName().length()
                    + 1 + getName().length());
            fullNameBuf.append(this.tableName);

            // much faster to append a char than a String
            fullNameBuf.append('.');
            fullNameBuf.append(this.name);
            this.fullName = fullNameBuf.toString();
            fullNameBuf = null;
        }

        return this.fullName;
    }

    /**
     * DOCUMENT ME!
     *
     * @return DOCUMENT ME!
     */
    public String getFullOriginalName() {
        getOriginalName();

        if (this.originalColumnName == null) {
            return null; // we don't have this information
        }

        if (this.fullName == null) {
            StringBuffer fullOriginalNameBuf = new StringBuffer(getOriginalTableName()
                                                                    .length()
                    + 1 + getOriginalName().length());
            fullOriginalNameBuf.append(this.originalTableName);

            // much faster to append a char than a String
            fullOriginalNameBuf.append('.');
            fullOriginalNameBuf.append(this.originalColumnName);
            this.fullOriginalName = fullOriginalNameBuf.toString();
            fullOriginalNameBuf = null;
        }

        return this.fullOriginalName;
    }

    /**
     * DOCUMENT ME!
     *
     * @return DOCUMENT ME!
     */
    public int getLength() {
        return this.length;
    }

    /**
     * DOCUMENT ME!
     *
     * @return DOCUMENT ME!
     */
    public boolean isMultipleKey() {
        return ((this.colFlag & 8) > 0);
    }

    /**
     * DOCUMENT ME!
     *
     * @return DOCUMENT ME!
     */
    public int getMysqlType() {
        return this.mysqlType;
    }

    /**
     * DOCUMENT ME!
     *
     * @return DOCUMENT ME!
     */
    public String getName() {
        if (this.name == null) {
            this.name = getStringFromBytes(this.nameStart, this.nameLength);
        }

        return this.name;
    }

    /**
     * DOCUMENT ME!
     *
     * @return DOCUMENT ME!
     */
    public String getOriginalName() {
        if ((this.originalColumnName == null)
                && (this.originalColumnNameStart != -1)
                && (this.originalColumnNameLength != -1)) {
            this.originalColumnName = getStringFromBytes(this.originalColumnNameStart,
                    this.originalColumnNameLength);
        }

        return this.originalColumnName;
    }

    /**
     * DOCUMENT ME!
     *
     * @return DOCUMENT ME!
     */
    public String getOriginalTableName() {
        if ((this.originalTableName == null)
                && (this.originalTableNameStart != -1)
                && (this.originalTableNameLength != -1)) {
            this.originalTableName = getStringFromBytes(this.originalTableNameStart,
                    this.originalTableNameLength);
        }

        return this.originalTableName;
    }

    /**
     * Returns amount of correction that
     * should be applied to the precision value.
     *
     * Different versions of MySQL report different
     * precision values.
     *
     * @return the amount to adjust precision value by.
     */
    public int getPrecisionAdjustFactor() {
        return this.precisionAdjustFactor;
    }

    /**
     * DOCUMENT ME!
     *
     * @return DOCUMENT ME!
     */
    public boolean isPrimaryKey() {
        return ((this.colFlag & 2) > 0);
    }

    /**
     * DOCUMENT ME!
     *
     * @return DOCUMENT ME!
     */
    public int getSQLType() {
        return this.sqlType;
    }

    /**
     * DOCUMENT ME!
     *
     * @return DOCUMENT ME!
     */
    public String getTable() {
        return getTableName();
    }

    /**
     * DOCUMENT ME!
     *
     * @return DOCUMENT ME!
     */
    public String getTableName() {
        if (this.tableName == null) {
            this.tableName = getStringFromBytes(this.tableNameStart, this.tableNameLength);
        }

        return this.tableName;
    }

    /**
     * DOCUMENT ME!
     *
     * @return DOCUMENT ME!
     */
    public boolean isUniqueKey() {
        return ((this.colFlag & 4) > 0);
    }

    /**
     * DOCUMENT ME!
     *
     * @return DOCUMENT ME!
     */
    public boolean isUnsigned() {
        return ((this.colFlag & 32) > 0);
    }

    /**
     * DOCUMENT ME!
     *
     * @return DOCUMENT ME!
     */
    public boolean isZeroFill() {
        return ((this.colFlag & 64) > 0);
    }

    /**
     * DOCUMENT ME!
     *
     * @return DOCUMENT ME!
     */
    public String toString() {
    	return this.getDatabaseName() + " . " +  this.getTableName() + "(" + this.getOriginalTableName() + ") . " + this.getName() + "(" + this.getOriginalName() + ")" + ", Mysql type: " + getMysqlType(); //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$ //$NON-NLS-4$ //$NON-NLS-5$ //$NON-NLS-6$
       
    }

    int getDecimals() {
        return this.colDecimals;
    }

    boolean isNotNull() {
        return ((this.colFlag & 1) > 0);
    }
    
    boolean isOpaqueBinary() throws SQLException {
    	
    	if (this.charsetIndex == 63 && isBinary()) {
    		return true;
    	}
    	
    	return (this.connection.versionMeetsMinimum(4, 1, 0) &&
    			"binary".equalsIgnoreCase(getCharacterSet()));
    			
    }
    /**
     * Is this field _definitely_ not writable?
     * 
     * @return true if this field can not be written to in an INSERT/UPDATE
     * statement.
     */
    boolean isReadOnly() throws SQLException {
    	if (this.connection.versionMeetsMinimum(4, 1, 0)) {
    		String orgColumnName = getOriginalName();
    		String orgTableName = getOriginalTableName();
    		
    		return !(orgColumnName != null && orgColumnName.length() > 0 &&
    				orgTableName != null && orgTableName.length() > 0);
    	}
    		
    	return false; // we can't tell definitively in this case.
    }
    
    void setMysqlType(int type) {
    	this.mysqlType = type;
    	this.sqlType = MysqlDefs.mysqlToJavaType(this.mysqlType);
    }

    /**
     * Create a string with the correct charset encoding from the
     * byte-buffer that contains the data for this field
     */
    private String getStringFromBytes(int stringStart, int stringLength) {
        if ((stringStart == -1) || (stringLength == -1)) {
            return null;
        }

        String stringVal = null;

        if (this.connection != null) {
            if (this.connection.getUseUnicode()) {
            	String encoding = this.connection.getCharacterSetMetadata();
                
                if (encoding == null) {
                	encoding = connection.getEncoding();
                }

                if (encoding != null) {
                    SingleByteCharsetConverter converter = null;

                    if (this.connection != null) {
                        converter = this.connection.getCharsetConverter(encoding);
                    }

                    if (converter != null) { // we have a converter
                        stringVal = converter.toString(this.buffer, stringStart,
                                stringLength);
                    } else {
                        // we have no converter, use JVM converter 
                        byte[] stringBytes = new byte[stringLength];

                        int endIndex = stringStart + stringLength;
                        int pos = 0;

                        for (int i = stringStart; i < endIndex; i++) {
                            stringBytes[pos++] = this.buffer[i];
                        }

                        try {
                            stringVal = new String(stringBytes, encoding);
                        } catch (UnsupportedEncodingException ue) {
                            throw new RuntimeException(
                                Messages.getString("Field.12") + encoding //$NON-NLS-1$
                                + Messages.getString("Field.13")); //$NON-NLS-1$
                        }
                    }
                } else {
                    // we have no encoding, use JVM standard charset
                    stringVal = StringUtils.toAsciiString(this.buffer, stringStart,
                            stringLength);
                }
            } else {
                // we are not using unicode, so use JVM standard charset 
                stringVal = StringUtils.toAsciiString(this.buffer, stringStart,
                        stringLength);
            }
        } else {
            // we don't have a connection, so punt 
            stringVal = StringUtils.toAsciiString(this.buffer, stringStart,
                    stringLength);
        }

        return stringVal;
    }

	//
	// MySQL only has one protocol-level BLOB type that it exposes
	// which is FIELD_TYPE_BLOB, although we can divine what the
	// actual type is by the length reported ...
	//
	private void setBlobTypeBasedOnLength() {
		 if (this.length == MysqlDefs.LENGTH_TINYBLOB) {
		 	this.mysqlType = MysqlDefs.FIELD_TYPE_TINY_BLOB;
		 } else if (this.length == MysqlDefs.LENGTH_BLOB) {
		 	this.mysqlType = MysqlDefs.FIELD_TYPE_BLOB;
		 } else if (this.length == MysqlDefs.LENGTH_MEDIUMBLOB) {
		 	this.mysqlType = MysqlDefs.FIELD_TYPE_MEDIUM_BLOB;
		 } else if (this.length == MysqlDefs.LENGTH_LONGBLOB) {
		 	this.mysqlType = MysqlDefs.FIELD_TYPE_LONG_BLOB;
		 }
	}
}