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postgresql
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There are a number of changes. The main ones are: 

return oid on insert
 handle all primitive data types
 handle single quotes and newlines in Strings
 handle null variables
 deal with non public and final variables (not very
   well, though)

Ken K
This commit is contained in:
Bruce Momjian 2001-05-24 15:48:32 +00:00
parent 23287c106d
commit 6f101c806b
1 changed files with 181 additions and 60 deletions
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241
src/interfaces/jdbc/org/postgresql/util/Serialize.java
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@ -23,16 +23,16 @@ public class Serialize
{
// This is the connection that the instance refers to
protected org.postgresql.Connection conn;
// This is the table name
protected String tableName;
// This is the class name
protected String className;
// This is the Class for this serialzed object
protected Class ourClass;
/**
* This creates an instance that can be used to serialize or deserialize
* a Java object from a PostgreSQL table.
@ -41,16 +41,16 @@ public class Serialize
{
try {
conn = c;
tableName = type.toLowerCase();
className = toClassName(type);
tableName = toPostgreSQL(type);
className = type;
ourClass = Class.forName(className);
} catch(ClassNotFoundException cnfe) {
throw new PSQLException("postgresql.serial.noclass",type);
}
// Second check, the type must be a table
boolean status = false;
ResultSet rs = conn.ExecSQL("select typname from pg_type,pg_class where typname=relname and typname='"+type+"'");
ResultSet rs = conn.ExecSQL("select typname from pg_type,pg_class where typname=relname and typname='" + tableName + "'");
if(rs!=null) {
if(rs.next())
status=true;
@ -59,10 +59,26 @@ public class Serialize
// This should never occur, as org.postgresql has it's own internal checks
if(!status)
throw new PSQLException("postgresql.serial.table",type);
// Finally cache the fields within the table
}
/**
* Constructor when Object is passed in
*/
public Serialize(org.postgresql.Connection c,Object o) throws SQLException
{
this(c, o.getClass().getName());
}
/**
* Constructor when Class is passed in
*/
public Serialize(org.postgresql.Connection c, Class cls) throws SQLException
{
this(c, cls.getName());
}
/**
* This fetches an object from a table, given it's OID
* @param oid The oid of the object
@ -73,14 +89,20 @@ public class Serialize
{
try {
Object obj = ourClass.newInstance();
// NB: we use java.lang.reflect here to prevent confusion with
// the org.postgresql.Field
java.lang.reflect.Field f[] = ourClass.getDeclaredFields();
// used getFields to get only public fields. We have no way to set values
// for other declarations. Maybe look for setFieldName() methods?
java.lang.reflect.Field f[] = ourClass.getFields();
boolean hasOID=false;
int oidFIELD=-1;
StringBuffer sb = new StringBuffer("select");
char sep=' ';
// build a select for the fields. Look for the oid field to use in the where
for(int i=0;i<f.length;i++) {
String n = f[i].getName();
if(n.equals("oid")) {
@ -95,13 +117,37 @@ public class Serialize
sb.append(tableName);
sb.append(" where oid=");
sb.append(oid);
DriverManager.println("store: "+sb.toString());
ResultSet rs = conn.ExecSQL(sb.toString());
if(rs!=null) {
if(rs.next()) {
for(int i=0;i<f.length;i++) {
f[i].set(obj,rs.getObject(i+1));
if ( !Modifier.isFinal(f[i].getModifiers()) ) {
if (f[i].getType().getName().equals("short")){
f[i].setShort(obj, rs.getShort(i+1));
}
else
if (f[i].getType().getName().equals("char")){
f[i].setChar(obj, rs.getString(i+1).toCharArray()[0]);
}
else
if (f[i].getType().getName().equals("byte")){
f[i].setByte(obj, rs.getByte(i+1));
}
else
// booleans come out of pgsql as a t or an f
if (f[i].getType().getName().equals("boolean")){
if ( rs.getString(i+1).equals("t"))
f[i].setBoolean(obj, true);
else
f[i].setBoolean(obj, false);
}
else{
f[i].set(obj,rs.getObject(i+1));
}
}
}
}
rs.close();
@ -114,7 +160,7 @@ public class Serialize
throw new SQLException(ie.toString());
}
}
/**
* This stores an object into a table, returning it's OID.<p>
*
@ -138,24 +184,27 @@ public class Serialize
try {
// NB: we use java.lang.reflect here to prevent confusion with
// the org.postgresql.Field
java.lang.reflect.Field f[] = ourClass.getDeclaredFields();
// don't save private fields since we would not be able to fetch them
java.lang.reflect.Field f[] = ourClass.getFields();
boolean hasOID=false;
int oidFIELD=-1;
boolean update=false;
// Find out if we have an oid value
for(int i=0;i<f.length;i++) {
String n = f[i].getName();
if(n.equals("oid")) {
hasOID=true;
oidFIELD=i;
// We are an update if oid != 0
update = f[i].getInt(o)>0;
}
}
StringBuffer sb = new StringBuffer(update?"update "+tableName+" set":"insert into "+tableName+" values ");
StringBuffer sb = new StringBuffer(update?"update "+tableName+" set":"insert into " + tableName);
char sep=update?' ':'(';
for(int i=0;i<f.length;i++) {
String n = f[i].getName();
@ -164,49 +213,108 @@ public class Serialize
sep=',';
if(update) {
sb.append('=');
if(f[i].getType().getName().equals("java.lang.String")) {
// handle unset values
if (f[i].get(o) == null)
sb.append("null");
else
if(f[i].getType().getName().equals("java.lang.String") ||
f[i].getType().getName().equals("char")) {
sb.append('\'');
sb.append(f[i].get(o).toString());
// don't allow single qoutes or newlines in the string
sb.append(fixString(f[i].get(o).toString()));
sb.append('\'');
} else
sb.append(f[i].get(o).toString());
}
}
if(!update) {
sb.append(") values ");
sep='(';
for(int i=0;i<f.length;i++) {
String n = f[i].getName();
if(f[i].getType().getName().equals("java.lang.String")) {
sb.append(sep);
sep=',';
// handle unset values
if (f[i].get(o) == null)
sb.append("null");
else
if(f[i].getType().getName().equals("java.lang.String") ||
f[i].getType().getName().equals("char")) {
sb.append('\'');
sb.append(f[i].get(o).toString());
// don't allow single quotes or newlines in the string
sb.append(fixString(f[i].get(o).toString()));
sb.append('\'');
} else
sb.append(f[i].get(o).toString());
}
sb.append(')');
}
DriverManager.println("store: "+sb.toString());
ResultSet rs = conn.ExecSQL(sb.toString());
if(rs!=null) {
rs.close();
}
org.postgresql.ResultSet rs = (org.postgresql.ResultSet)conn.ExecSQL(sb.toString());
// fetch the OID for returning
int oid=0;
if(hasOID) {
// set the oid in the object
// If an update use the existing oid in the object
f[oidFIELD].setInt(o,oid);
}
else {
String statStr = rs.getStatusString();
oid = Integer.parseInt(statStr.substring(statStr.indexOf(" ") + 1, statStr.lastIndexOf(" ")));
}
if(rs!=null) {
rs.close();
}
return oid;
} catch(IllegalAccessException iae) {
throw new SQLException(iae.toString());
}
}
/**
*
*/
private String fixString(String s) {
int idx = -1;
// handle null
if (s == null)
return "";
// if the string has single quotes in it escape them
if ((idx = s.indexOf("'")) > -1) {
StringBuffer buf = new StringBuffer();
StringTokenizer tok = new StringTokenizer(s, "'");
// handle quote as 1St charater
if (idx > 0) buf.append(tok.nextToken());
while(tok.hasMoreTokens())
buf.append("\\'").append(tok.nextToken());
s = buf.toString();
}
// if the string has newlines in it convert them to \n
if ((idx = s.indexOf("\n")) > -1) {
StringBuffer buf = new StringBuffer();
StringTokenizer tok = new StringTokenizer(s, "\n");
if (idx > 0) buf.append(tok.nextToken());
while(tok.hasMoreTokens())
buf.append("\\n").append(tok.nextToken());
s = buf.toString();
}
return s;
}
/**
* This method is not used by the driver, but it creates a table, given
* a Serializable Java Object. It should be used before serializing any
@ -219,7 +327,7 @@ public class Serialize
{
create(con,o.getClass());
}
/**
* This method is not used by the driver, but it creates a table, given
* a Serializable Java Object. It should be used before serializing any
@ -232,49 +340,50 @@ public class Serialize
{
if(c.isInterface())
throw new PSQLException("postgresql.serial.interface");
// See if the table exists
String tableName = toPostgreSQL(c.getName());
ResultSet rs = con.ExecSQL("select relname from pg_class where relname = '"+tableName+"'");
if(!rs.next()) {
DriverManager.println("found "+rs.getString(1));
// DriverManager.println("found "+rs.getString(1));
// No entries returned, so the table doesn't exist
StringBuffer sb = new StringBuffer("create table ");
sb.append(tableName);
char sep='(';
java.lang.reflect.Field[] fields = c.getDeclaredFields();
// java.lang.reflect.Field[] fields = c.getDeclaredFields();
java.lang.reflect.Field[] fields = c.getFields();
for(int i=0;i<fields.length;i++) {
Class type = fields[i].getType();
// oid is a special field
if(!fields[i].getName().equals("oid")) {
sb.append(sep);
sb.append(fields[i].getName());
sb.append(' ');
sep=',';
if(type.isArray()) {
// array handling
} else {
// convert the java type to org.postgresql, recursing if a class
// is found
String n = fields[i].getType().getName();
String n = type.getName();
int j=0;
for(;j<tp.length && !tp[j][0].equals(n);j++);
if(j<tp.length)
sb.append(tp[j][1]);
else {
create(con,fields[i].getType());
create(con, type);
sb.append(toPostgreSQL(n));
}
}
}
}
sb.append(")");
// Now create the table
DriverManager.println("Serialize.create:"+sb);
con.ExecSQL(sb.toString());
@ -283,22 +392,26 @@ public class Serialize
DriverManager.println("Serialize.create: table "+tableName+" exists, skipping");
}
}
// This is used to translate between Java primitives and PostgreSQL types.
private static final String tp[][] = {
{"boolean", "int1"},
// {"boolean", "int1"},
{"boolean", "bool"},
{"double", "float8"},
{"float", "float4"},
{"int", "int4"},
{"long", "int4"},
// {"long", "int4"},
{"long", "int8"},
{"short", "int2"},
{"java.lang.String", "text"},
{"java.lang.Integer", "int4"},
{"java.lang.Float", "float4"},
{"java.lang.Double", "float8"},
{"java.lang.Short", "int2"}
{"java.lang.Short", "int2"},
{"char", "char"},
{"byte", "int2"}
};
/**
* This converts a Java Class name to a org.postgresql table, by replacing . with
* _<p>
@ -314,17 +427,25 @@ public class Serialize
public static String toPostgreSQL(String name) throws SQLException
{
name = name.toLowerCase();
if(name.indexOf("_")>-1)
throw new PSQLException("postgresql.serial.underscore");
if(name.length()>32)
throw new PSQLException("postgresql.serial.namelength",name,new Integer(name.length()));
// Postgres table names can only be 32 character long
// If the full class name with package is too long
// then just use the class name. If the class name is
// too long throw an exception.
if(name.length() > 32) {
name = name.substring(name.lastIndexOf(".") + 1);
if(name.length()>32)
throw new PSQLException("postgresql.serial.namelength",name,new Integer(name.length()));
}
return name.replace('.','_');
}
/**
* This converts a org.postgresql table to a Java Class name, by replacing _ with
* .<p>
@ -338,5 +459,5 @@ public class Serialize
name = name.toLowerCase();
return name.replace('_','.');
}
}