sql的封装，不需要使用StringBuffer进行字符串拼接

package com.l5m.customtags.sql; import java.util.Collection; import java.util.List; public abstract class SqlBean { public final static int NUMBER = 0; // no '' public final static int VARCHAR = 1; // has '' protected List<String> columnList; protected StringBuilder sql; protected StringBuilder whereSql = null; protected String tableName; protected String schema; public SqlBean(String schema, String tableName){ this.tableName = tableName; this.schema = schema; } public void append(String oper, String condition){ if (this.whereSql == null) { this.whereSql = new StringBuilder(); this.whereSql.append(" WHERE ").append(condition); } else { this.whereSql.append(" ").append(oper).append(" ").append(condition); } } public void and(String condition){ append("AND",condition); } public void andNum(String prefix,Object suffix){ append("AND",prefix+suffix.toString()); } public void andStr(String prefix,Object suffix){ append("AND",prefix+changeToChar(suffix)); } public void or(String condition){ append("OR",condition); } public void orNum(String prefix,Object suffix){ append("OR",prefix+suffix.toString()); } public void orStr(String prefix,Object suffix){ append("OR",prefix+changeToChar(suffix)); } public String convert(String value, int dataType) { return dataType == NUMBER ? value : "'" + value + "'"; } public String changeToChar(Object o){ return "'"+o.toString()+"'"; } public void clear(){ if (this.whereSql != null) this.whereSql = null; } public static String join(Collection<String> colletion) { StringBuilder sb = new StringBuilder(); for (String str : colletion) { sb.append(str).append(","); } sb.deleteCharAt(sb.length() - 1); return sb.toString(); } public static String collectionToSql(Collection<?> collection, String sepraor, boolean isVarchar){ if(collection == null || collection.isEmpty()) return "(null)"; StringBuilder builder = new StringBuilder("("); for(Object o : collection){ if(isVarchar) builder.append("'").append(o.toString().replaceAll("'", "''")).append("'").append(sepraor); else builder.append(o.toString()).append(sepraor); } builder.replace(builder.length()-1, builder.length(), ")"); return builder.toString(); } public static String collectionToSql(Collection<?> collection, boolean isVarchar){ if(collection == null || collection.isEmpty()) return "(null)"; StringBuilder builder = new StringBuilder("("); for(Object o : collection){ if(isVarchar) builder.append("'").append(o.toString().replaceAll("'", "''")).append("'").append(","); else builder.append(o.toString()).append(","); } builder.replace(builder.length()-1, builder.length(), ")"); return builder.toString(); } public void setColumnList(String column){ setColumnList(column.split(",")); } public void setColumnList(List<String> columnList) { this.columnList = columnList; } public void setColumnList(String[] columns){ for(String column:columns){ columnList.add(column); } } public void addCompany(String companyId){ append("AND", "COMPANY_ID = "+companyId); } public abstract String toString(); }